Warm Season Grasses

Posted on November 5, 2026 by CAHNR Communications

Warm season grasses are often an important component of wildlife habitat improvement programs. Areas of warm season grasses provide cover for nesting, brood-rearing, roosting and escape for a variety of song and game birds. Small mammals like rabbits also benefit from their cover. Because of their bunching growth patterns, warm season grasses tend to have a fairly high percentage of bare ground between plants. These bare areas are important because they provide for ease of movement essential both for escape and food collection. At the same time, the soil is held in place reducing the potential for erosion.

Birds may feed on insects concentrated in warm season grass plantings as well as plant parts including seeds. Generally these native grasses mature to form a 1 to 3 foot high ground cover that holds up well over the winter providing an insulating effect which is important for many wildlife species.

For prime wildlife habitat, warm season grasses are generally used in conjunction with plantings and management of cool season grasses, forbes and woody plants for maximum habitat diversity. Due to their growth habits, the establishment and maintenance of warm season grasses requires some diligence on the part of landowners. Left unattended, stands become too dense for good wildlife habitat as plant material accumulates or becomes overrun by more aggressive cool season grasses and forbes.

Properly managed stands of warm season grasses can be cut for hay and provide grazing during the hot, dry mid-summer months. Since, most of their growth occurs from midJune through mid-August, refrain from haying between April 15th though August 1st. Although, like most plants, warm season grasses prefer deep, fertile, well-drained soils, they will tolerate sandy soils, acidic conditions and low phosphorus sites.

Common Species of Warm Season Grasses

Little Bluestem – Schizachyrium scoparium is a long-lived, low maintenance bunchgrass that reaches from 1 ½ to 5 feet in height. Plants are slender and erect with a bluish-green to purplish color at the base of their somewhat bulbous stems. After frost, whole plants take on a becoming reddish hue. Stems are hairy and strongly flattened at the base. The inflorescence is a spike-like raceme with bristly awns and fluffy white seeds. Little bluestem will form a dense cover on sites with adequate moisture but thins out on drier sites. The seeds are favored by small mammals and waterfowl.

Switchgrass – Panicum virgatum is a rhizomatous grass that reaches 3 to 5 feet. Although bunch-like in appearance, switchgrass produces short rhizomes under grazing. Late season leafy reqrowth arises from basal tillers and shoots will emerge along the lower stems at leaf nodes. This perennial grass can tolerate poorly drained soils and can withstand occasional flooding and perched water tables. Forage quality is good when immature but both palatability and nutrient content decline after seed head formation.

Big Bluestem – Andropogon geradi is an erect, perennial bunchgrass growing from 3 to 6 feet. It often takes on an attractive reddish purple color at maturity. Growing points generally are low to the ground with early season buds forming at basal nodes and from short, scaly rhizomes. They become elevated as seed heads form. Big bluestem can be used on sites with excessively well drained soils. It also retains its palatability after reaching maturity better than switchgrass or Indiangrass.

Indiangrass – Sorghastrum nutans is a slow spreading, upright, perennial grass that matures at 3 to 6 feet and produces short, knobby rhizomes. It begins growth later than switchgrass or big bluestem but produces good quality forage throughout most of the summer. Moderately well-drained soils are preferred but Indiangrass can withstand occasional flooding. Palatability is moderate after seed head formation.

Eastern Gamagrass – Tripsacum dactyloides is a tall, erect bunchgrass that grows from 6 to 12 feet tall. It is related to corn and is among the earliest of warm season grasses to begin growth each spring. Plants form large clumps with sizeable space between plants. Eastern gamagrass could be used for hay or grazing but mowing is difficult over the rough, clumpy stands, and this warm season grass species requires a long, late summer rest period. Ideal growing sites include fertile bottomlands, alongside streambeds and in swampy areas as deep soils with high water holding capacity are necessary for good development. Eastern gamagrass is very slow to establish and has a high seed dormancy rate.

The species listed above are readily available from commercial sources. The Connecticut office of Natural Resources Conservation Service recommends shorter warm season grass species for wildlife habitat enhancement. It is believed that at one time, Connecticut contained short grass prairie ecosystems Also, along roadsides and other disturbed areas, shorter warm grass species are common. Some recommended shorter warm season grass species include little bluestem (mentioned above), Coastal little bluestem (Schizachyrium scoparium subsp. littoralis), broom sedge (Andropogon virginicus L.), beard grass (Andropogon elliotti), side oats grama (Bouteloua curtipendula), blue grama (Bouteloua gracilis), June grass (Koeleria macrantha), dropseed (Sporobolus indicus) and buffalo grass (Buchloe dactyloides).

Finding seed sources for the shorter warm season grasses can be more difficult but should become easier as the demand for conservation mixes increases. The NRCS also strongly recommends purchasing seed from local or, at least regional sources. This may also be challenging for some species but plantings are generally more successful if locally adapted seed sources are used. Appendix A lists several seed/plant sources.

Seeding Warm Season Grasses

In general, warm season grasses are slow to establish requiring a minimum of 2 years for adequate stand development. They are poor competitors with cool season grasses and weed species. Close attention must be paid to their growth requirements for successful establishment. When evaluating potential establishment sites, determine if warm season grasses are already present. Intensive management may be all that is needed for warm season grasses to be restored.

For new seedings, begin by selecting a site with low weed pressure, or control the weeds on the area to be seeded. Weed control can often be achieved by prescribed burning or tilling the soil. An ideal location might be where row crops were previously grown and competing weeds controlled. Warm season grasses have been successfully seeded into conventionally prepared seedbeds, using no-till practices in small grain stubble, and notill practices into pastures where herbicides were applied to kill existing sod.

A soil fertility test is also recommended 6 months to a year before seeding. Warm season grasses are tolerant of low pH soils, however, better results are generally obtained when the soil pH is around 6.0. Adjustments to the soil pH are made through additions of ground limestone.

Before seeding, incorporate phosphorus and potassium according to soil test recommendations. Do not apply nitrogen at seeding as it will stimulate weed competition which is detrimental to these slow establishing grasses. In the case of very low fertility site, about 30 pounds of nitrogen per acre can be applied in July after the grasses have started growing if the stand is vigorous and few weeds are present.

It is recommended that warm season grass seed be purchased by pounds of pure live seed (PLS). This should be listed on the bag of seed along with the germination rate and percentages of dormant seeds, weed seeds and inert materials. The CT Department of Environmental Protection suggests only purchasing seed originating no more than 100 miles north or 200 miles south of the project site. Depending on the species, seeding rates range from 5 to 12 lbs. of PLS per acre. Wildflowers and legumes can be added to the seed mix at about 1 lb PLS per acre. Seeds require contact with bare mineral soil to germinate.

Table 1. Suggested Warm Season Grass Cultivars for Connecticut *

Species	Cultivar	Geographic Use Area
Big Bluestem	Kaw	Southern VT/NH & South
	Niagra	All
Little Bluestem	Aldous	NY & South
	Camper	NY & South
Salt meadow cordgrass	Avalon	VA to NH, Coastal Wetlands
Smooth cordgrass	Bayshore	VA to NH
Deertongue	Tioga	All
Eastern gamagrass	Pete	All
Sideoats gramma	El Reno	NY & South
	Trailway	Southern New England & North
Indiangrass	NE-54	NY & North
	Rumsey	VA & North
Sand lovegrass	Bend	Central VT, NH & South
	NE-27	NY & South
Coastal panicgrass	Atlantic	All
Switchgrass	Blackwell	NY & South
	Cave-In-Rock	NY & South
	Shelter	WV to Southern NH

*From Managing Grasslands, Shrublands, and Young Forest Habitats for Wildlife: A Guide for the Northeast. Ed. by Oehler, J.D., Covell, D. F., Capel, S. and Long, B. 2006. Northeast Upland Technical Committee

May and early June seedings of warm season grasses are recommended for the Connecticut area. Minimum air and soil temperatures should be between 60 to 65 degrees F, and 50 degrees F, respectively. Early May seedings give plants more time during their first growing season for stand development. Seedings made later than mid-June may not be successful due to competition from cool season grasses and weed species and dry, summertime conditions.

Warm Season Grass Maintenance

The key to successfully establishing warm season grasses is patience. Young seedlings spend most of their first two years establishing extensive root systems resulting in sparse top growth. Two full growing seasons should pass before an evaluation of stand establishment can generally be made. Ideally there should be one vigorous plant per square foot by the second growing season. According to both the CT Department of Environmental Protection and the Natural Resources Conservation Service, it may take two to three years for a stand to be fully established.

It is critical to control competition from weeds during the first two years of stand establishment. This can be done by mowing, herbicides and prescribed burning. Burning is not recommended until years three or four. Overgrazing should be avoided.

Although warm season grasses are more tolerant of low soil fertility levels, studies have shown moderate amounts of nutrients to be beneficial. Plants respond with increased levels of productivity, vigor and persistence. Generally 40 pounds per acre of nitrogen, phosphorus and potassium is recommended annually. To fulfill this requirement, apply 400 pounds of 10-10-10 or the equivalent per acre. Fertilizer is applied when grasses are three to four inches high, usually in mid-May. Soil fertility tests can be conducted every three to five years to monitor soil pH and fertility levels.

Warm season grasses serve as an important habitat for many species of grassland birds, mammals and other animals. Restoration efforts are supported by a number of government programs including the USDA Wildlife Habitat Incentives Program, Grassland Reserve Program, DEP Landowner Incentives Program, Conservation Reserve Program, Wetlands Reserve Program and the U. S. Fish and Wildlife Partners Program. Contact the CT Department of Environmental Protection, the Natural Resources Conservation Service or the U. S. Department of Fish and Wildlife to find out about technical assistance or funding opportunities.

Appendix A. Sources for warm season grass seed and plants.

New England Wetland Plants
820 West Street
Amherst, MA 01002
(413) 548-8000
www.newp.com

Natural Attraction Project, Inc.
Denise Ciastko
PO Box 113
Canterbury, CT 06331
Email: info@naturalattractionproject.com
www.napinc.org

Ernst Conservation Seeds
9006 Mercer Pike
Meadville, PA 16335-9299
(800) 873-3321
www.ernstseed.com

References

Barnhart, S. K. 1994. Warm-Season Grasses for Hay and Pasture. Iowa State University. Fact Sheet.
Bartholomew, H. H., Sulc, R. M., Hendershot, R. and Cline, J. Perennial Warm Season Grasses For Ohio. Ohio State University Fact Sheet AGF-022-95.
DeLong, C. and Brittingham, M. 2002. Warm Season Grasses and Wildlife. Pennsylvania Wildlife No. 12. Penn State College of Agricultural Sciences, Agricultural Research and Cooperative Extension.
Guillard, K. 2006. University of Connecticut. Personal communication.
Hall, M. H. 1994. Warm-Season Grasses. Penn State University. Agronomy Facts 29.
Native Warm Season Grasses for Wildlife. 1993 Missouri Department of Conservation.
Oehler, J.D., Covell, D. F., Capel, S. and Long, B., Editors. 2006. Managing Grasslands, Shrublands, and Young Forest Habitats for Wildlife: A Guide for the Northeast. Northeast Upland Habitat Technical Committee.
Taylor, R. 2006. University of Delaware. Personal communication.

By Dawn Pettinelli, Assistant Extension Educator

The author wishes to thank Howard B. Denslow, Resource Conservationist and Nels Barrett, Ph.D. of the USDA Natural Resources Conservation Service, Tolland, CT for reviewing this fact sheet.

Suggested Fertilizer Practices for Trees, Shrubs, Vines and Groundcovers

Posted on November 5, 2026 by CAHNR Communications

Woody plants growing in their native habitats get their nutrients from fallen litter, soil minerals and beneficial micro-organisms through their extensive root systems. The ornamentals grown in landscape beds or lawns are more likely to experience competition for nutrients from neighboring plants and often encounter less than favorable soil conditions especially in new developments. Also, plants that originated in other parts of the country or abroad may have different, and sometimes, higher fertility requirements than our native vegetation. Most homeowners rake up leaves and other plant debris so the nutrients are carted away and not recycled. Properly fertilized plants are more likely to survive a stress period (drought, severe winter, and insect or disease attack) than plants grown in soil with inadequate nutrient levels. Fertilizer, however, will not overcome poor cultural conditions such as inadequate light, water-logged, compacted or droughty soil, poor plant selection, air pollution, misuse of pesticides, etc. It is wise to have your soil tested before applying fertilizer. Do not use lawn fertilizer containing broadleaved weed killers (herbicide) near or under woody plants.

When to Apply Fertilizer

The timing of fertilizer applications is partially dependent on the type of fertilizer used. In general, plants can be fertilized in spring (after April 15th) or in fall (before October 15th). Fertilizing from July through September should generally be avoided unless the plant is under severe stress due to a nutrient deficiency. Any new growth that results from fertilizing during this period often does not have time to harden off before the onset of winter, and the result is tip dieback of the new growth.

If using a slow release, inorganic fertilizer or a natural/organic fertilizer, one spring or fall application is generally sufficient for the year. When more typical synthetic, granular fertilizers are used (like 10-6-4 or 10-10-10), the application can be split into thirds with equal portions applied in mid-April, early June and September. Soluble fertilizers that are dissolved in water and then applied to plants need to be put down on a biweekly or monthly basis depending on package directions.

How Much Fertilizer to Apply

Without a soil test follow the fertilizer recommendations in the table below shows the varying rates of fertilizer to apply. The smaller amount in a given range should supply enough nutrients for maintenance and adequate growth. Use this amount if plants have reached sufficient size. The larger amount in a given range will result in more growth. This may be desirable for plants that have not reached their desired or mature size. Flowering trees and shrubs (crabapple, dogwood, rhododendron, etc.) should receive the smaller amount of fertilizer listed to avoid lush vegetative growth at the expense of flower bud formation. Flower bud formation is essential if flowering is to occur the following season.

Watering After Fertilizing

Ideally, fertilizer should be applied just before a gentle, soaking rain is predicted so that the fertilizer can move into the plant’s root zone. Irrigate the fertilized areas if no rain or only a shower is forecasted.

Table 1. Fertilizer Recommendations for Trees, Shrubs and Groundcovers

Row	Fertilizer Grade	Deciduous Trees, Shrubs, Groundcovers and Vines (lbs. of fertilizer per 100 sq. ft.)	Evergreen Trees and Shrubs; Narrowleaf evergreens, Rhododendrons and Azaleas (lbs. of fertilizer per 100 sq. ft.)
1	10-6-4 or 10-10-10	1-2	½ – 1
2	5-10-10	2-4	1-2
3	5-10-5	2-4	1-2

Use the fertilizer recommended at the rate indicated or the equivalent from other sources.
One pound of nitrogen can be supplied by 8.3 lbs. of bloodmeal or 17 lbs. of cottonseed meal. One pound of phosphorus can be supplied by 8 lbs. of bonemeal or 4 lbs. of rock phosphate. One pound of potassium can be supplied by 14.5 lbs of greensand.

Weight of Fertilizer

Fertilizer recommendations are made in pounds per 100 square feet. The following tips may be useful: (1) one level, unpacked cup of a synthetic granular fertilizer like 10-10-10, 10-6-4 or 5-10-5 weighs approximately ½ pound. (2) One level, unpacked cup of an organic blended fertilizer weighs about 1/3 pound. (3) One level, unpacked cup of rock dusts like greensand or rock phosphate weighs ¾ pound.

Substituting Fertilizers

It is possible to substitute a fertilizer of one grade for that of another grade. For example, 10-20-20 can be used in place of 5-10-10. An important adjustment must be made, however. The 10-20-20 contains twice as much nitrogen (first number) as 5-10-10. Therefore, 10-20-20 should be applied at half the rate suggested for 5-10-10. Never apply more nitrogen than recommended as plant injury may occur.

Shrub Fertilization

The root system of most shrubs is located in the area under the plant and extends a few feet beyond the spread of the branches. Therefore, the fertilizer should be broadcast in this area. Avoid injury to the plant by keeping the fertilizer a few inches from the stem. The amount of fertilizer to apply is calculated from Table 1 after measuring the area covered by the plants. See Figures 1 and 2.

Tree Fertilization

The root system of a tree can spread from 1 1/2 to 2 times its height. For example, a tree with a height of 40 feet could have a root spread of 60 to 80 feet. This means the roots will spread 30 to 40 feet away from the trunk and puts a large percentage of the fine feeder roots well beyond the tree’s drip line. The preferred method of fertilizing trees is to spread the fertilizer on the surface over the entire root system of the plant. This allows more of the root system to pick up the nutrients and eliminates zones of high fertilizer concentration which can damage the fine feeder roots. When calculating the area to be fertilized, estimate the width of the crown then increase this number by 25 to 50 percent for optimal coverage of the tree’s root system. The amount of fertilizer to apply is calculated from Table 1 after measuring the area covered by the plants. See Figures 1 and 2. Trees growing in a regularly fertilized lawn will probably not require additional fertilizer.

Ericaceous Plants

The ericaceous plants (rhododendron, azalea, laurel, andromeda, etc.) are shallow, fibrous-rooted plants that can be damaged by heavy applications of fertilizer. Apply only the lower rates of fertilizer for plants of this group. An important cultural practice that is often neglected for this group of plants is maintaining the soil’s organic matter content. This is easily accomplished by adding an inch or two of organic mulch every year or so.

Vines

A vine will “travel” a long distance from where it was planted alongside a wall or under a trellis. The roots radiate in all directions from the ground unless the vine is planted against a building or some structure that restricts the growth of the roots. Stay at least one foot away from the stem when broadcasting the fertilizer. Cover an area at least 10 ft. x 10 ft. (100 sq. ft.) around the stem for large established vines. If the ground is bare or planted with shrubs, scratch the fertilizer into the soil to a depth of ½ to 1 inch. Vines growing in or near a regularly fertilized lawn will probably not require additional fertilizer.

Groundcovers

Determine the area of the groundcover bed. Broadcast the amount of fertilizer evenly over the area. Apply the fertilizer when the foliage is dry to prevent injury. Fertilizer sticking to wet foliage can cause “burning”, and should be brushed or hosed off.

By E. Marrotte, 1995, Revised by D. Pettinelli 2015

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Suggested Fertilizer Practices for Tree Fruits

Posted on November 5, 2026 by CAHNR Communications

Tree fruits are attractive as well as tasty additions to the home landscape. There are numerous varieties of apples, pears and stone fruits to choose from that are well suited to our climate conditions. Tree fruits are also available on dwarf and semi-dwarf rootstocks where planting space is limited.

For best production, tree fruits require a minimum of six hours of direct sunlight each day. Trees exposed to early morning sun may have less disease problems as the nighttime dew that covers the leaves will evaporate quicker. Avoid planting tree fruits in low lying areas or cold air pockets. The blossoms may be damaged by late frosts.

Ideal soils for tree fruits are deep, well-drained sandy loams, although most tree fruits can tolerate coarser or heavier soils. Good drainage is imperative, however, or root growth will be impaired and roots will be unable to support the weight of bearing trees. Tree fruits prefer soils with a pH ranging from 6.0 to 6.5, and containing moderate levels of organic matter.

Typically, a purchased fruit tree consists of two genetically different individuals that have been grafted together. The ‘scion’ is the aboveground part that produces the type of fruit desired. The ‘rootstock’ is the underground portion and the variety of rootstock used determines both the tree’s ultimate size and how long it will take to bear fruit. The point where the two parts are connected is referred to as the graft union. When planting tree fruits the graft union should be 2 to 4 inches above ground. If the graft union is placed at or below ground level, the scion wood may root and trees on dwarf or semi-dwarf root stocks would grow to full size.

Six Months To One Year Before Planting

Have the soil tested. Follow the soil test recommendations to adjust the pH into the desired range for tree fruits. Dolomitic limestone, that contains both calcium and magnesium, is the most readily available liming material and is most commonly used to raise the soil pH. If soil test magnesium levels are above optimum, however, a calcitic limestone should be selected.

It is important that calcium levels be maintained in the desired range as physiological problems like corking and bitter pit of apples may result from inadequate calcium supplies. Adequate calcium in the soil also improves the cold hardiness of peach trees.

Depending on environmental conditions, it may take 9 months or more for a substantial pH change to occur from applications of limestone. If at all possible, work the limestone into the top 8 to 12 inches of soil in areas where tree fruits are to be planted. Retest the soil before planting if a large adjustment in soil pH was necessary.

Year Of Planting

Consider having the soil tested if you have not already done so. If limestone is recommended at this time, it is most practical to mix it with the soil that is to be placed around the roots at planting time. For every 4 pounds of limestone per 100 sq. ft. recommended, apply 1 tablespoon of limestone per cubic foot of soil. For example, if the recommendation on the computer sheet is 12 pounds of limestone per 100 sq. ft., add 3 tablespoons of limestone to each cubic foot of soil placed around tree roots.

If soil phosphorus levels are below optimum, add superphosphate (0-20-0) at the rate of 1 to 2 oz. (1/8 to ¼ cup) OR triple superphosphate (0-46-0) at the rate of ½ to 1 oz. (1 to 2 tbsp.) OR bonemeal (1-11-0) at the rate of 2 to 4 oz. (1/4 to ½ cup) per cubic foot of soil used to back fill the planting hole. Mix any limestone or phosphorus thoroughly with the soil that is to be placed around the roots when planting.

Without a soil test, after the tree is planted, apply ¼ cup of 10-10-10 or the equivalent from other sources around the plant. Spread the material evenly in an area 4 feet in diameter. Repeat the application in 4 to 6 weeks, but not later than the middle of June.

Second And Third Year

Without a soil test, apply, per plant, 1 to 1 ¼ cup 10-10-10, or the equivalent from other sources in the second year, and 1 ½ to 2 cups in the third year. Split the application applying half in mid-April and half 4 to 6 weeks later. Spread evenly in an area 5 to 6 feet in diameter.

Fourth Year And Older

If plants have been fertilize regularly in previous years, it may not be necessary to add additional phosphorus to the soil unless a soil test indicates it is below optimum. Nitrogen and potassium, however, are generally added on a yearly basis. Any available nitrogen is used up quickly by plants, fixed by microorganisms, volatilized or leached from the soil, and therefore needs to be added each year. Adequate potassium levels have been linked to improved cold hardiness.

Amounts of nitrogen needed annually for young trees can be based on the tree’s spread (canopy diameter) as shown in Table 1. For pears, reduce of the amount by 25 to 50 percent to decrease the incidence of fire blight. Apply the fertilizer within the limits of branch spread about mid-April. On very sandy soils, a split application may be more effective with one half of the fertilizer applied in early April and the rest applied 4 to 6 weeks later. When trees have grown to desired mature size, a 50 to 75 percent reduction in amounts applied may be needed to avoid excessive vegetative growth. Table 1 values are for trees that have not grown as large as desired. In general, mature apple trees should put on between 8 and 12 inches of growth each year, pears about 8 to 15 inches and stone fruits like peaches between 12 to 18 inches. If soil test potassium is below optimum, use a 10-10-10.

Table 1. Annual Fertilizer Rates for Vigorous Growth of Tree Fruits

Tree Spread (ft. diameter)	Amount
8	1 lb. 3 oz.
10	1 lb. 14 oz.
12	2 lb. 11 oz.
14	3 lb. 10 oz.
15	4 lb. 3 oz.
16	4 lb. 14 oz.
18	6 lb. 1 oz.
20	7 lb. 8 oz.
22	9 lb. 1 oz.
24	10 lb. 13 oz.
26	12 lb. 11 oz.
28	14 lb. 11 oz.
30	16 lb. 14 oz.

Note: 8 oz. = ½ lb. = 1 cup of 10-6-4.

*For pears, reduce rates by 25 to 50 percent. For dwarf trees, reduce rates by 50 percent. For mature trees, reduce rates by 50 to 75 percent.

For bearing apple and pear trees, a boron fertilizer can be applied to the ground every three years. Apply Borax (10 to 12% boron) as shown in Table 2. Do not exceed the indicated amounts as plant injury may result. Apply in a circle around the tree about 4 to 15 feet out from the trunk depending on the tree’s size. For closely planted trees, a band application on two sides of the row is satisfactory. Plants fertilized with natural organic sources rarely need additional boron.

Table 2. Rates of Borax to Apply Once Every Three Years.

Tree Spread (ft. diameter)	Ounces* borax per tree (10-12% boron)
6	0.4
8	0.7
10	1.1
12	1.6
14	2.2
16	2.8
18	3.6
20	4.4
22	5.3
24	6.3
26	7.5
28	8.6
30	10.0

*One ounce of granulated borax equals about 3 tablespoons.

Note:

10 lbs of 10-10-10 will supply plants with 1 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft. (Phosphate is a form of phosphorus; Potash is a form of potassium)
10 lbs of 10-6-4 will supply plants with 1 lb. of Nitrogen (N), about 1/2 lb. of Phosphate (P₂O₅) and about 1/2 lb. of Potash (K₂O) per 1000 sq. ft.

To Supply Nutrients Using Natural/Organic Sources Use The Following Equivalents:

1 lb. of Nitrogen can be supplied by 8.3 lbs. of bloodmeal (12-0-0) or 11 lbs. of corn gluten (9-0-0).
1 lb. of Phosphate can be supplied by 6.75 lbs. of bonemeal (3-15-0) or 33.5 lbs. of rock phosphate (0-3-0).
1 lb. of Potash can be supplied by 25 lbs. of kelp meal (1-0-4) or 4.5 lbs. of sul-po-mag* (0-0-22).

Keep in mind that the NPK analysis of natural organic products may vary by producer and adjust your application rates accordingly.

*Note: May need to be special or mail ordered.

By Dawn Pettinelli, Assistant Extension Educator, Dept. of Plant Science & Landscape Architecture 12/05, revised 12/15

Suggested Fertilizer Practices For Vegetables and Herbs

Posted on November 5, 2026 by CAHNR Communications

The enclosed soil test report provides the pH and available nutrient levels present in your soil at the time of sample collection. Based on these results, limestone and fertilizer recommendations are made for the vegetable crops you listed. Soil tests are unable to identify problems associated with poor cultural practices, damage from insects, disease or environmental stress, or injuries caused by the misuse of pesticides. Contact the UConn Home and Garden Education Center at 877‐486‐6271 or through their website for assistance with these problems.

Soil pH and Limestone

The pH measures the acidity or alkalinity of a soil. The majority of vegetables prefer a slightly acidic soil with a pH ranging from 6.0 to 6.8. Ground limestone is generally used to correct acidic soil conditions, although some gardeners prefer the less dusty pelletized limestone. Cost is the major difference between the two forms; application rates and reactions times are similar.

Most widely available is dolomitic limestone, containing both calcium and magnesium carbonates. If reported magnesium levels are above optimum and the addition of limestone is recommended to raise the pH, a calcitic limestone which contains only calcium carbonates would be your best choice.

Note: One cup limestone weighs about 3/4 lb.

Hydrated lime (calcium hydroxide) is not recommended because it is caustic to humans, plants and soil organisms. More recently soluble forms of calcium (like Solu-Cal and MAG-I-CAL) have become commercially available. These products do increase the amount of soluble calcium in the soil for plant uptake but to date, studies indicate that they do not increase the pH appreciably faster than ground or pelletized limestone products. They may be useful in preventing blossom end rot in tomatoes if soil tests indicate a need for calcium. Always follow the label directions if applying these products.

Wood ashes can be used as a substitute for limestone. Apply at approximately 1.5 times the recommended rate of limestone. For example, 7.5 pounds of wood ashes could be substituted for 5 pounds of limestone. Do not apply wood ashes if the pH is over 6.8.

Note: One cup wood ashes equal about 1/3 lb.

Fertilizers

Fertilizer recommendations are based on soil test results and the kinds of vegetables grown. Your soil test report will recommend varying amounts of several widely available fertilizer grades. The fertilizer grade is denoted by the three numbers on the front of the fertilizer bag. These numbers represent the percent of total nitrogen (N), available phosphate (P₂O₅) and water soluble potassium or potash (K₂O) contained in the fertilizer. They will always be listed in this exact order. A fertilizer with the analysis 5‐10‐10 would contain 5% N, 10% P₂O₅, and 10% K₂O.

Recommendations for most vegetable gardens are for a complete fertilizer meaning that it contains the three major plant nutrients: nitrogen, phosphorus and potassium. Occasionally when the soil test indicates very low or very high values for a certain nutrient, a single nutrient fertilizer is recommended. Examples would be superphosphate (0‐20‐0) or bloodmeal (12-0-0).

Fertilizers other than those recommended, including various natural organic fertilizers, can be used provided they supply nutrients in about the same amounts and ratios as the recommended fertilizer. For example, a 10‐20‐20 could be used in place of a 5‐10‐10, but since it is twice as concentrated you would only use one‐half as much. Fertilizers formulated for vegetable gardens generally contain amounts of nitrogen less than or equal to the amount of phosphorus (i.e. 5‐10‐5 or 10‐10‐10). This is because phosphorus promotes flowering and fruiting. Too much nitrogen will stimulate green leafy growth at the expense of vegetable production.

Note: If your results state that both phosphorus and potassium levels are above optimum, only a nitrogen recommendation will be provided. For each pound of nitrogen recommended per 1000 sq. ft. you may use your choice of 8.3 lbs. of bloodmeal (12‐0‐0), 11 lbs. of corn gluten (9-0-0), or 2.2 lbs. of urea (46‐0‐0).

Applying Fertilizers

Fertilizer recommendations are given in increments of 1000 sq. ft. Therefore, you need to determine the size of your garden before spreading the fertilizer. The length multiplied by the width of the garden will give you the total area. For instance, a garden 25 feet long and 10 feet wide equals 250 sq. ft. If the recommendation given is for 8 pounds of 5‐10‐10 per 1000 sq. ft., you would only use one quarter as much, or 2 pounds in your 250 square foot garden.

Note: One cup of a granular synthetic fertilizer weighs about 1/2 pound.

Fertilizers are spread over the garden area before planting in the spring. A spade or rototiller can be used to mix the fertilizer into the top 4 to 6 inches of soil. Long season crops like sweet corn and tomatoes, and vine crops such as pumpkins and melons, may benefit from a side dressing of fertilizer during the growing season. Apply the recommended rate in a band along rows. Do this by placing fertilizer 6 inches on each side of a row of crops. Scratch in lightly to avoid root damage and water thoroughly.

Note:

10 lbs. of 10-10-10 will supply plants with 1 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft. (Phosphate is a form of phosphorus; Potash is a form of potassium)
10 lbs. of 5-10-10 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft.
10 lbs. of 5-10-5 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1/2 lb. of Potash (K₂O) per 1000 sq. ft.

To Supply Nutrients Using Natural/Organic Sources Use The Following Equivalents:

1 lb. of Nitrogen can be supplied by 8.3 lbs. of bloodmeal (12-0-0) or 11 lbs. of corn gluten (9-0-0)
1 lb. of Phosphate can be supplied by 6.75 lbs. of bonemeal (3-15-0) or 33.5 lbs. of rock phosphate (0-3-0)
1 lb. of Potash can be supplied by 25 lbs. of kelp meal (1-0-4) or 4.5 lbs. of sul-po-mag (0-0-22)* or 2 lbs. of potassium sulfate (0-0-50)**

Keep in mind that the NPK analysis of natural organic products may vary by producer and adjust your application rates accordingly.

*Note: May need to be special or mail ordered.
**Note: Not all sources are certified for organic production.

By D. Pettinelli, 2001, Revised 2023

Suggested Fertilizer Practices for Grapes

Posted on November 5, 2026November 5, 2026 by CAHNR Communications

Grape varieties suitable for cultivation by home gardeners in Connecticut include American, European and French-American hybrids. American grapes that are hardy in Connecticut are mainly derived from the fox grape (Vitis labrusca). Concord, Catawba, Reliance and Niagara are popular American varieties.

French-American hybrids are crosses between the Old World viniferas and Native American grape species. Both these hybrids and the European vinifera grapes (V. vinifera) are primarily grown for wine making purposes. Grape varieties of European origin may not be reliably winter hardy throughout the state. Several French-American hybrids like Seyval Blanc and Vidal Blanc exhibit greater cold tolerance.

All grape cultivars have similar phosphorus and potassium requirements. American varieties may need greater amounts of nitrogen to perform well. Soil pH preferences, however, differ considerably. American grape varieties require an acidic soil with an ideal pH of 5.5. They have a relatively high iron requirement and iron solubility increases under acidic conditions. European vinifera varieties prefer the soil pH to be about 6.5. European-American hybrids vary in their pH preference depending on which parent they resemble most.

Once established, grapevines can be productive for 40 years or more. Adequate soil preparation before planting will contribute to successful vine establishment.

Six months to one year before planting:

Have the soil tested. Add any necessary limestone at the rate recommended on the soil test results. Liming to a pH higher than 5.5 for American varieties or 6.5 for European varieties is not recommended. If soil test magnesium values are below optimum and the pH needs to be raised, use a dolomitic limestone. This type of limestone contains both calcium and magnesium. In situations where the soil pH level does not need to be changed but soil magnesium levels are below optimum, incorporate 1 pound of Epsom salts (MgSO₄) per 100 sq. ft. Retest soil every 3 years to monitor pH levels.

If soil test phosphorus is below optimum, apply triple superphosphate (0-45-0) at the rate of ½ pound (1 cup) or bonemeal (1-11-0) at the rate of 2 ¼ lbs. (6 ¾ cups) per 100 sq. ft. If soil test potassium is below optimum, add potassium sulfate (0-0-50)* at a rate of ¾ lb. (1 ½ cups) or sul-po-mag (0-0-22) at the rate of 1 ½ lbs. (2 cups) per 100 square feet. Incorporate all necessary amendments to a depth of 6 to 8 inches. Retest soil one month before planting.

Fertilizers

Year of planting:

Without a soil test, apply 2 ounces (1/4 cup) of 10-10-10 per vine soon after growth begins, and again about 4 weeks later. Spread evenly over an area 4 to 5 feet in diameter.

Second year:

Without a soil test, Apply 4 ounces (1/2 cup) of 10-10-10 per vine soon after growth begins, and again about 4 weeks later. Spread evenly over an area 4 to 5 feet in diameter.

Third year and older:

Without a soil test, apply 1/2 lb. (1 cup) of 10-10-10 per each European grapevine or 1 pound (2 cups) of 10-10-10 per each American grapevine at budbreak. Spread evenly over an area 3 to 5 feet wide on each side of vine.

If soil test potassium and phosphorus are above optimum, apply only a source of nitrogen to the vines. Urea (46-0-0) at 2 to 3 ounces (1/2 cup) or bloodmeal (12-0-0) at 8 ounces (1 ½ cups) per vine will supply the desired amounts of nitrogen. Excessive vegetative growth indicates the need to reduce the amount of nitrogen by one half or omit entirely for one to two years.

Once every 3 years a borax application may be beneficial. Borax (10 to 12% boron) should be applied at not more than ¾ ounce (about 2 tablespoons) per 100 sq. ft. Excess boron can cause plant injury. Borax can be dissolved in water and sprayed onto the ground. In order to prevent damage to the sprayer, strain out sediments after borax has dissolved. Note that plants fertilized with natural/organic sources of nutrients rarely will require added boron.

*Avoid use of potassium chloride (KCl) as chloride injury may occur.

Note:

10 lbs. of 10-10-10 will supply plants with 1 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft. (Phosphate is a form of phosphorus; Potash is a form of potassium).
10 lbs. of 5-10-10 will supply plants with ½ lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft.
10 lbs. of 5-10-5 will supply plants with ½ lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and ½ lb. of Potash (K₂O) per 1000 sq. ft.

To supply nutrients using natural/organic sources use the following equivalents:

1 lb. of Nitrogen can be supplied by 8.3 lbs. of bloodmeal (12-0-0) or 11 lbs. of corn gluten (9-0-0)
1 lb. of Phosphate can be supplied by 6.75 lbs. of bonemeal (3-15-0) or 33.5 lbs. of rock phosphate (0-3-0)
1 lb. of Potash can be supplied by 25 lbs. of kelp meal (1-0-4) or 4.5 lbs. of sul-po-mag (0-0-22)* or 2 lbs. of potassium sulfate (0-0-50)**

Keep in mind that the NPK analysis of natural organic products may vary by producer and adjust your application rates accordingly.

*Note: May need to be special or mail ordered.
**Note: Not all sources are certified for organic production.

By D. Pettinelli, Associate Extension Educator, 2001. Revised 2015, 2023.

Suggested Fertilizer Practices for Flowers

Posted on November 4, 2026 by CAHNR Communications

(Annuals, Perennials, Bulbs, Roses, Ornamental Grasses & Wild Flowers)

Flowers enhance the garden with their color and fragrance. Many flowering plants can produce blossoms throughout the growing season if their cultural requirements are met. Among those requirements are essential nutrients for plant growth and development. Nutrients are added to garden soils primarily through fertilization. Either natural or synthetic fertilizers, or a combination of the two types, can be used to meet the nutrient needs of flowering plants.

Each year the number of species of flowering plants available for the home garden increases. Some plants have very specific soil pH and fertility requirements. Others can tolerate a wide range of levels. Limestone and fertilizer recommendations may have to be modified accordingly. It is always a wise idea to research the cultural requirements of plants before adding them to the landscape.

I. Soil pH, Limestone and Sulfur applications.

The soil pH refers to the measurement of soil acidity. A soil pH of 7.0 is considered neutral. Values less than 7.0 reflect acidic soil conditions while those above indicate alkalinity. The majority of flowering plants will grow well within a soil pH range of 5.5 to 7.0 with a target pH of 6.5. It would be lower for native wildflowers and ferns reflecting their adaptation to more acidic conditions.

Recommendations for ground limestone will be made if the soil pH needs to be increased. Limestone raises the soil pH, reduces soil acidity, increases the calcium and, in the case of dolomitic limestone, also increases the magnesium level in the soil. Either ground or pelletized limestone is used to correct acid soil conditions. Cost is the major difference between the two forms; application rates and soil reaction times are similar.

Limestone may be applied any time the ground is not frozen. Whenever possible, incorporate the ground limestone into the top 6 to 8 inches of soil. If more than 10 lbs. of ground limestone per 100 sq. ft. is recommended, and it can only be applied to the soil surface, a split application is suggested.

Occasionally the soil pH level is too high for the particular plants being grown and the soil test report will recommend appropriate amounts of sulfur or aluminum sulfate to lower it. Generally, it takes 6 to 9 months for the soil pH to change following either limestone or sulfur applications.

Note: One cup of limestone weighs about 3/4 lb.

II. Fertilizers

Fertilizer recommendations are based on soil test results and on the type of flowering plant being grown. Your soil test report will recommend varying amounts of several widely available fertilizer grades. The fertilizer grade is denoted by the three numbers on the front of a fertilizer container. These numbers refer to the percent by dry weight of total nitrogen (N), available phosphate (P2O5), and water soluble potassium (K2O) contained in package of fertilizer. They are always listed in this same order. A fertilizer with an analysis of 5-10-5 would contain 5% N, 10% P205 and 5% K20.

Recommendations for flowering plants are for a complete fertilizers which is one that contains the three major plant nutrients nitrogen, phosphorus and potassium. Occasionally when the soil test indicates very low or very high values for a certain nutrient, a single nutrient source would be recommended. Examples would be superphotsphate (0-20-0) or bloodmeal (12-0-0).

Fertilizers other than those recommended, including various natural organic materials, can be used provided they supply nutrients in about the same amounts and ratios as the recommended fertilizer. For example, a 3-4-4 could be used in place of a 10-10-10 at 3 times the rate as it is only one-third as concentrated.

In general, fertilizers formulated for flowering plants would contain amounts of nitrogen less than or equal to the amounts of phosphorus (i.e. 10-10-10 or 5-10-5). This is because phosphorus encourages flowering. Too much nitrogen will stimulate green leafy growth at the expense of flower production. Also, the recommendations are made for granular fertilizer formulations. These will generally supply nutrients to the plants for about 6 to 8 weeks. During periods of excessive rainfall or frequent irrigation, the nutrients may be leached out of the soil and fertilizer may need to be reapplied.

III. How and When to Fertilize

Use the grade of fertilizer (or equivalent) recommended on the enclosed soil test report at the times of year listed below for the type of flowering plants being grown. For new flower beds, work the fertilizer into the top 4 to 6 inches of soil before planting. For established plantings, spread the fertilizer evenly around the plants and lightly scratch it into the soil, then water thoroughly. Pull back the mulch around plants so the fertilizer is applied to the soil and not on top of the mulch.

Fertilizer recommendations are given in increments of 100 sq. ft. Therefore, you need to determine the size of your garden before spreading the fertilizer. The length multiplied by the width of the garden will give you the total area. For instance a garden 5 feet wide and 10 feet across would cover 50 sq. ft. Often flower gardens are irregularly shaped. Just do your best to approximate the square footage.

Note: One cup of a granular synthetic fertilizer weighs about 1/2 pound.

A. Flowers (annuals, perennials, ornamental grass, bulbs)

Annuals – Apply fertilizer at the recommended rate during flower bed preparation. Make a second application at the same rate 6 to 8 weeks later. Annual selections that will continue blooming into fall may benefit from a third application at the same rate made in late August. Keep in mind that other cultural requirements aside from adequate nutrients must be met for plants to continue optimum growth.
Perennials and Ornamental Grasses (new plantings) – Apply fertilizer at the recommended rate during flower bed preparation. Make a second application at the same rate 6 to 8 weeks later.
Perennials and Ornamental Grasses (established) – Apply fertilizer at the recommended rate when growth resumes in the spring. Perennials with long lasting foliage or extended bloom periods may benefit from a second application at the same rate 6 to 8 weeks later.
Spring Flowering Bulbs – Apply fertilizer at the recommended rate as soon as new growth emerges in the spring. Also apply fertilizer at the same rate when preparing beds in late August or early September.
Summer Flowering Bulbs – Apply fertilizer at the recommended rate at planting time or, in the case of hardy summer flowering bulbs, when growth resumes in the spring. Make a second application at the same rate after flowering for plants with short flowering periods, such as gladioli. For plants with long flowering periods like dahlias and cannas, make a second fertilizer application at the same rate in mid-July.

B. Roses

Follow the instructions on the soil test report. Make separate applications of fertilizer at the recommended rate in May, June and July. Do not fertilize after mid-July as new growth may be encouraged. It most likely will not have time to harden off properly in the fall and will be very susceptible to winter kill.

C. Wildflowers

Wildflowers that are native to New England’s woodlands or meadows generally have low nutrient requirements. Apply the recommended amount of fertilizer once in the spring as new growth begins, or during bed preparation. Some wildflower species have very specific cultural requirements that may not be met with our more generalized recommendations. Gardeners may have to research the needs of individual species.

Note:

10 lbs. or 10-10-10 will supply plants with 1 lb. of Nitrogen (N), 1 lb. of Phosphate (P2O5) and 1 lb. of Potash (K2O) per 1000 sq. ft. (Phosphate is a form of phosphorus; Potash is a form of potassium.)
10 lbs. of 5-10-10 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate (P2O5) and 1 lb. of Potash (K2O) per 1000 sq. ft.
10 lbs. of 5-10-5 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate (P2O5) and 1/2 lb. of Potash (K2O) per 1000 sq. ft.

To Supply Nutrients Using Natural/Organic Sources Use the Following Equivalents:

1 lb. of Nitrogen can be supplied by 8.3 lbs. of bloodmeal (12-0-0) or 11 lbs. of corn gluten (9-0-0)
1 lb. of Phosphate can be supplied by 6.75 lbs. of bonemeal (3-15-0) or 33.5 lbs. of rock phosphate (0-3-0)
1 lb. of Potash can be supplied by 25 lbs. of kelp meal (1-0-4) or 4.5 lbs. of sul-po-mag (0-0-22)* or 2 lbs. of potassium sulfate (0-0-50)* **

Keep in mind that the NPK analysis of natural organic products may vary by producer and adjust your application rates accordingly.

*Note: May need to be special or mail ordered.
**Note: Not all sources are certified for organic production.

By D. Pettinelli, 2001, Revised 2015

Suggested Fertilizer Practices for Blueberries

Posted on November 4, 2026November 4, 2026 by CAHNR Communications

Blueberries are popular in home gardens because of their flavorful fruit and manageable size. For best results, plant blueberries in an acidic (pH 4.5 to 5.4), well drained, sandy loam fortified with organic matter.

Blueberry plants have fine, fibrous roots that are primarily found in the top 8 to 12 inches of soil. These fibrous roots lack root hairs present on most other plant species and because of this, blueberry plants have a limited ability to absorb nutrients and water. This situation is alleviated somewhat by a special fungal organism present in the soil called mycorrhizae. A particular mycorrhizal fungus lives both in and on blueberry plant roots, and aids in the uptake of nutrients and water. Clear cultivation and prolonged use of synthetic fertilizer will reduce mycorrhizal numbers.

The fibrous roots of blueberries also have much difficulty penetrating compacted soils, so loosen soils and add organic matter before planting. The ideal organic matter content for growing blueberries is between 4 and 7%. Avoid sites that are subjected to extreme wet or dry conditions. Organic mulches are suggested to retain moisture, moderate soil temperatures and retard weeds.

Six Months To One Year Before Planting

Have a soil test done. If soil pH is not in the range necessary for blueberries, add limestone or sulfur* at the rate recommended on the soil test report. Use dolomitic limestone that contains magnesium as well as calcium if it is necessary to raise the soil pH.

If the soil test results for magnesium are in the below optimum category but limestone is not recommended, apply 10 ounces of Epsom salts per 100 sq. ft.

If the soil test results for phosphorus are in the below optimum, apply triple superphosphate (046-0) at a rate of 1/2 lbs. (1 cup), or bonemeal (1-11-0) at a rate of 2 lbs. (6 cups) per 100 sq. ft.

If soil test results for potassium are below optimum, add potassium sulfate (0-0-50) at a rate of 3/4 lbs. (1 1/2 cups) or sul-po-mag (0-0-22) at a rate of 1.5 lbs. (2 cups) per 100 sq. ft.

Incorporate all necessary amendments to a depth of 6 to 8 inches. Retest soil before planting.

Changing The pH In Established Plantings

Mixing amendments such as ground limestone or sulfur* into the soil of an established blueberry planting is difficult because of the shallow, dense root system. Surface application is suggested with increments of 1/2 lb. (1 cup) sulfur or 5 lbs. (7 cups) of ground limestone per 100 sq. ft. applied in the spring and again in the fall until the full recommended amount is added to the soil. Recheck the pH one-year after the last sulfur or limestone addition.

Fertilizers

Fertilizers that supply nitrogen in the ammonium form are preferred over those supplying nitrogen as nitrate because blueberries are sensitive to nitrate and injury may occur. Use a 7-7-7 or 4-3-4 fertilizer or one of similar grade made for acid-loving plants.

Year of planting

Three to 4 weeks after planting, apply 1 ounce (1/8 cup) of a 7-7-7 or 2 oz (1/4 cup) 4-3-3 or other similar grade acidifying fertilizer per plant. Spread the fertilizer evenly over the ground in a 15 to 18 inch circle around the plant. Blueberries are easily injured by excess fertilizer or concentrated placement. Lightly scratch in and water. Repeat at the same rate in 4 to 6 weeks.

Second year

Apply, per plant, 2 ounces (1/4 cup) of a 7-7-7 or 4 oz (1/2 cup) 6-4-4 or other similar grade acidifying fertilizer in April and again about 4 to 6 weeks later. Lightly scratch in and water.

Third year and older

Fertilize in spring shortly after buds break. Each year increase the amount of fertilizer by 2 or 4 oz, respectively, to a maximum of 12 or 24 ounces per plant for blueberry bushes that have been in place 6 years or more.

If growth seems excessive, reduce the rate of fertilization by 1/3 to 1/2. As the diameter of the blueberry bush increases in size, be sure to increase the area of ground around the plant to which fertilizer is applied.

*Aluminum sulfate can also be used to acidify the soil. To make the same pH change as with sulfur, multiply the recommended rate for sulfur by 6. However, because aluminum sulfate is a soluble salt, it can burn roots. For this reason, sulfur is preferred on planted ground. If aluminum sulfate is used on planted ground, it should be applied in 4 to 5 equal portions at 3 to 4 week intervals, each application followed by irrigation.

Note:

10 lbs. of 10-10-10 will supply plants with 1 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft. (Phosphate is a form of phosphorus; Potash is a form of potassium)
10 lbs. of 5-10-10 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1 lb. of Potash (K₂O) per 1000 sq. ft.
10 lbs. of 5-10-5 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate (P₂O₅) and 1/2 lb. of Potash (K₂O) per 1000 sq. ft.

To Supply Nutrients Using Natural/Organic Sources Use The Following Equivalents

1 lb. of Nitrogen can be supplied by 8.3 lbs of bloodmeal (12-0-0) or 11 lbs. of corn gluten (9-0-0).
1 lb. of Phosphate can be supplied by 6.75 lbs. of bonemeal (3-15-0) or 33.5 lbs. of rock phosphate (0-3-0).
1 lb. of Potash can be supplied by 25 lbs of kelp meal (1-0-4) or 4.5 lbs. of sul-po-mag (0-0-22)* or 2 lbs. of potassium sulfate (0-0-50)* **

Keep in mind that the NPK analysis of natural organic products may vary by producer and adjust your application rates accordingly.

*Note: May need to be special or mail ordered.
**Note: Not all sources are certified for organic production.

By D. Pettinelli, 2001, Revised 2015, 2023 UConn Soil Nutrient Analysis Lab

Suggested Fertilizer Practices for Lawns

Posted on November 4, 2026 by CAHNR Communications

The enclosed soil test report provides limestone and fertilizer recommendations for your lawn. Also provided are the pH and available nutrients of the soil sample you sent to our laboratory. The limestone and fertilizer recommendations are based on the pH and available nutrients of your soil.

Soil tests cannot identify lawn problems due to insects, diseases, poor cultural practices, environmental stress or misuse of pesticides. Contact the UConn Home Garden Education Center‘s website or call them at (877) 486-6271 for assistance with these problems.

It is essential to determine the area to be covered before purchasing or applying limestone and fertilizers. The area of square or rectangular shaped lawns can be easily calculated by multiplying the length times the width of the area in feet. To calculate the square footage of irregularly shaped lawns, divide your yard into smaller areas that are almost square or rectangular, measure them separately and add together for total square feet.

Lawn maintenance fertilizers usually have grades like 32-0-4, 29- 0-4 or 10-0-6. Higher amounts of nitrogen in lawn maintenance fertilizers reflect a turfgrass plant’s greater need for this nutrient. Note that lawn maintenance fertilizers sold in Connecticut contain 0% phosphorus. This is due to 2013 legislation that prohibits the addition of phosphorus fertilizers to established lawns except when recommended by a soil test performed within 2 years. Phosphorus may be added when seeding or sodding a new lawn or when overseeding an existing lawn. For more information, see the fact sheet Your Lawn and the New Phosphorus Law. Except for deficiency situations, the amount of potassium found in maintenance fertilizers is sufficient for good turf growth. If additional phosphorus or potassium is needed, recommended grades and rates will be listed on your soil test results.

Proper nitrogen fertilization is especially important for optimal turf establishment and growth. The amount of nitrogen in your soil sample is not measured by our standard nutrient analysis. This is because nitrogen levels are not reliable predictors of the nitrogen fertilizer needs of turfgrass. Nitrogen fertilizer recommendations for lawns are based on the amount of nitrogen removal by the grass plants during the growing season.

Two forms of nitrogen may be found in lawn fertilizers: readily available water soluble nitrogen or slow release water insoluble nitrogen (WIN). An ideal lawn fertilizers will contain both water soluble and water insoluble forms of nitrogen. Water soluble forms of nitrogen are rapidly available to turf grasses, but also readily subjected to leaching. Fertilizers containing at least 40% WIN will provide your lawn with a steady, continuous supply of nitrogen while reducing the potential for contamination of ground water supplies. A number of natural organic lawn fertilizers are available at local garden centers and retail stores. Much of the nitrogen in organic fertilizers is also in a slow release form. Lawns fertilized with slow release or natural organic sources of nitrogen tend to grow more evenly. Quick release, water soluble nitrogen often results in heavy flushes of new growth that are more susceptible to disease problems and also require more frequent mowings.

Amount And Timing Of Lawn Fertilizers

Cool season turf grass species, including Kentucky bluegrass, fescues and perennial ryegrass, require about 2 pounds of nitrogen per 1000 sq. ft. each year for satisfactory growth if clippings are left in place. Grass clippings add nutrients and organic matter to the soil. Contrary to popular belief, they do not contribute to thatch buildup. If clippings are removed, 3 pounds of N per 1000 sq. ft. may be needed.

Never apply more than 1 pound of water soluble N per 1000 sq. ft. at one time. Slow release fertilizers, including natural organic fertilizers and synthetic controlled release products, may be applied at higher rates (follow manufacturer’s instructions) because much of their nitrogen is water insoluble. Ideal times to fertilize lawns are in May and early September. A third application may be needed in June if clippings are removed.

Shaded lawn areas planted with fescues require less nitrogen because reduced light limits growth. A single fertilizer application of 1 pound of N per 1000 sq. ft. either in May or early September is sufficient for these areas.

Do not apply fertilizer after mid-October or before April 15th. Application of nitrogen fertilizer, especially water soluble nitrogen, too early or late in the season leaches from the soil before it can be used by turfgrass and can contaminate ground and surface water supplies.

How Much Fertilizer To Buy?

Follow these steps to determine the amount of fertilizer to purchase for an application of 1 pound of nitrogen per 1000 sq. ft.:

Calculate the square feet of lawn surface to be covered.
Select the fertilizer you want to use and determine the percent nitrogen in your fertilizer by looking at the first of the 3 numbers on the package. For example, a 21-0-4 contains 21% nitrogen. How much fertilizer you need to apply depends upon the nitrogen content of that particular fertilizer.
Use Table 1 to find the recommended pounds of fertilizer with that % nitrogen to cover 1000 sq. ft. For example, if you wanted to use a 21-0-4, you would find 21 in column 1, then go directly across to column 2 and see that 5 pounds of a fertilizer containing 21% nitrogen will cover 1000 sq. ft.
If your lawn area is 7000 sq. ft. then you would purchase and apply 35 pounds of 21-0-4 fertilizer. This is calculated by multiplying the 5 pounds of 21-0-4 fertilizer per 1000 sq. ft. times 7 units of 1000 sq. ft. (your 7000 sq. ft. of lawn area).
So 35 pounds of a 21-0-4 fertilizer would be applied to 7000 sq. ft. of lawn area to provide 1 pound of nitrogen per 1000 sq. ft.

Table 1. Recommended Rates of Maintenance Fertilizers

% Nitrogen in Organic or Synthetic Fertilizer	Recommended Fertilizer Rate (lbs./1,000 sq. ft.)
1	100
2	50
3	35
4	25
5	20
6	17
7	14
8	13
9	11
10	10
11	9
12–13	8
14–15	7
16–18	6
19–22	5
23–27	4
28–38	3

Soil pH And Liming Lawns

Soil pH is a measurement of the soil’s acidity or alkalinity. A pH of 7.0 is neutral, values below 7.0 are considered acidic while those greater than 7.0 are alkaline. The pH of the soil influences both the quality and vigor of turfgrasses. The ideal pH range for turfgrasses is between 6.0 and 7.0. If soil pH is below or above this range, nutrient availability may be reduced, and turfgrass growth and quality might not be optimal.

Ground limestone is generally used to correct acidic soil conditions, although some homeowners may prefer the less dusty pelletized limestone. Cost is the major difference between the two forms; application rates and reaction times are similar.

Dolomitic limestone, which contains both calcium and magnesium carbonates, is the most common liming material in our area. Occasionally, magnesium levels are above optimum but the soil pH needs to be increased. In this instance, a calcitic limestone that contains only calcium carbonate could be used.

Apply the recommended amount of limestone to increase the pH of your soil. Limestone can be applied any time the ground is not frozen except during periods of severe drought. While limestone supplies calcium and/or magnesium, it does not reduce the need for lawn fertilization. Also, the presence of moss does not necessarily indicate acidic soil conditions. Read the fact sheet Moss Control on the UConn Home & Garden Education Center’s website (www. ladybug.uconn.edu) if moss is a problem.

A maintenance application of 50 pounds of limestone per 1000 square feet can be applied every 2 to 3 years to maintain the pH of your soil. Single applications of limestone to established lawn surfaces should be limited to 50 to 75 pounds per 1000 sq. ft. Reapply at 1- to 6-month intervals until the total recommended amount is administered. For new lawns, the entire amount recommended can be tilled into the top 6 inches of soil before planting.

By Dawn Pettinelli, Assistant Extension Educator 2001, Revised 2015

Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Gregory J. Weidemann, Cooperative Extension System, University of Connecticut, Storrs. The Connecticut Cooperative Extension System is an equal opportunity employer and program provider. To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, Stop Code 9410, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964

Suggested Fertilizer Practices for Strawberries

Posted on November 4, 2026November 4, 2026 by CAHNR Communications

Strawberries are a choice fruit crop for many home gardeners. The low-growing plants are reliable and quick to produce. Strawberries should be planted in full sun for maximum yield. June-bearers provide a delicious supply of fruit from late spring through early summer, while day-neutral types produce berries throughout the summer.

The strawberry is a shallow-rooted perennial. More than 75 percent of its root system can often be found in the top 6 inches of soil. Because of this, strawberries tend to be quite sensitive to both excess water and drought conditions. They grow best when planted on fertile, well-drained soils that contain at least 6 percent organic matter. Organic matter should be incorporated into sandy soils to increase moisture retention.

Sites that tend to stay wet may not be suitable for strawberries unless raised beds are constructed. Water saturated soils prevent necessary oxygen from entering the root zone and roots may die. Diseases, especially red stele, are also more likely to occur under these conditions. Avoid growing strawberries where tomatoes, potatoes, peppers, eggplants, raspberries or strawberries were recently grown. The insect and/or disease problems carried over may cause substantial damage to strawberry plantings.

Six months to one year before planting:

It is strongly recommended that a soil test be performed six months to a year before planting and the soil be amended s according to the results of the test. When the soil pH, nutrients and organic matter are in the range preferred by strawberries, plants can get more quickly established and will typically be healthier and more productive.

Strawberries prefer a slightly acidic soil with a pH ranging from 6.0 to 6.3. If it is necessary to adjust the soil pH, apply the amount of ground limestone recommended on the soil test report. It is generally advisable to use a dolomitic limestone that contains both calcium and magnesium, especially if the soil has below optimum magnesium levels.

If soil test magnesium levels are optimum or above, a calcitic limestone can be substituted if increasing pH is necessary. Build up the organic matter levels by adding an inch of peat moss, leaf-based compost or other available materials. If a high nutrient manure-based compost is used, retest the soil one month after adding it to check if any more nutrients, in the form of chemical or natural organic fertilizer should be added.

If soil test results for potassium are below optimum, apply potassium chloride (0-0-60) or potassium sulfate (0-0-43) at a rate of about 7.5 lbs. or sul-po-mag (0-0-22) at a rate of 14 lbs., per 1000 sq. ft. If soil test results for phosphorus are below optimum, apply, triple superphosphate (0-46-0) at the rate of 5 lbs. or bonemeal (1-11-0) at the rate of 20 lbs. per 1000 square feet. Incorporate all necessary amendments thoroughly to a depth of 6 to 8 inches. Retest the soil before planting.

Boron is one of the most commonly deficient micronutrients in strawberry plantings. If boron was not added to the soil in the past 3 to 4 years, an application of borax (10-12 % boron) may be beneficial. For every 100 sq. ft. of intended strawberry bed, mix ¾ of an ounce (about 2 tablespoons) of borax into a gallon of water. Do not overapply as excess boron can cause plant injury. Soils regularly amended with compost or natural organic fertilizers generally contain sufficient boron for strawberries.

Year of Planting:

Without a soil test, about two weeks before planting, incorporate 20 lbs. of 5-10-10 (or the equivalent from other sources) for each 1000 sq. ft. of planting bed. Six to eight weeks after the first fertilizer application, apply 10 lbs. of 5-10-10 (or equivalent) per 1000 sq. ft.; spreading the fertilizer in a 6 inch band on each side of a row of strawberry plants. Repeat this rate again in late August. Brush or wash off any fertilizer granules that land on the foliage to avoid leaf injury.

Fruiting Year:

Avoid use of nitrogen fertilizer the spring before harvest as it may result in large, soft berries, excessive vegetative growth, and increase susceptibility of plants and fruits to diseases. However, if plants are a light shade of green and are not growing well, an application of 5 lbs. of 5-10-10 or 7.5 lbs. bloodmeal (12-0-0) (or equivalent) per 1000 sq. ft. may be beneficial.

June-bearing strawberry plantings are renovated after harvest. Cut back leaves, thin plants, and remove weeds, then apply 10 to 20 lbs. of 10-10-10 (or equivalent) per 1000 sq. ft. It is important that plants receive at least 1 inch of water per week following fertilization to encourage strong, healthy new growth and to avoid salt injury. In years of adequate moisture, either from natural rainfall or supplemental irrigation, fertilize strawberry beds again in late August with 5 lbs. 10-10-10 (or equivalent) per 1000 sq. ft. Do not fertilize after August 31st. This post harvest fertilization is repeated each year after harvest and renovation. Proper cultural practices should keep June-bearing strawberries productive for at least 3 to 5 years.

Fertilizers for day-neutral strawberries:

Day-neutral strawberry varieties can produce fruit throughout the summer so they require a steady supply of nutrients for optimum growth and development without a soil test. Apply 10 lbs. of 10-10-10 (or equivalent) per 1000 sq. ft. in mid-June, mid-July and again in late August.

Note:

10 lbs. of 10-10-10 will supply plants with 1 lb. of Nitrogen (N), 1 lb. of Phosphate (P2O5) and 1 lb. of Potash (K2O) per 1000 sq. ft. (Phosphate is a form of phosphorus; Potash is a form of potassium.)
10 lbs. of 5-10-10 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate ( P2O5) and 1 lb. of Potash (K2O) per 1000 sq. ft.
10 lbs. of 5-10-5 will supply plants with 1/2 lb. of Nitrogen (N), 1 lb. of Phosphate ( P2O5) and 1/2 lb. of Potash (K2O) per 1000 sq. ft.

To supply nutrients using natural/organic sources use the following equivalents:

1 lb. of Nitrogen can be supplied by 8.3 lbs. of bloodmeal (12-0-0) or 11 lbs. of corn gluten (9-0-0).
1 lb. of Phosphate can be supplied by 6.75 lbs. of bonemeal (3-15-0) or 33.5 lbs. of rock phosphate (0-3-0)
1 lb. of Potash can be supplied by 25 lbs. of kelp meal (1-0-4) or 4.5 lbs. of sul-po-mag (0-0-22)* or 2 lbs. of potassium sulfate (0-0-50)* **

*Note: May need to be special or mail ordered.
**Note: Not all sources are certified for organic production.

Keep in mind that the NPK analysis of natural organic products may vary by producer and adjust your application rates accordingly.

By D. Pettinelli, 2001, Revised 2015

Liming and Fertilizing Forage Crops in Connecticut

Posted on November 4, 2026 by CAHNR Communications

The Need for Lime in Connecticut

Nearly all naturally occurring Connecticut soils are very strongly to strongly acid (pH 4.5-5.5). Only a few of our soils are of limestone origin and not strongly acid. To produce crops efficiently, limestone must be applied to correct existing soil acidity. Subsequently, enough must be added to maintain a soil condition slightly acid to neutral in reaction.

Soil acidity occurs both naturally and as a result of cropping practices. Soil acidity is reduced naturally when rainfall leaches calcium and magnesium from the soil. Connecticut receives about 48 inches of rainfall annually, which is sufficient to lower pH considerably over a few years. The main cropping practice that lowers the pH of the soil is the application of nitrogen (N) fertilizer in the form of urea or fertilizers containing ammonium. These fertilizers reduce the pH of soils when soil microorganisms convert the urea or ammonium to nitrate and release hydrogen, which lowers pH. Harvesting forage, whether by machine, or through grazing, also removes large amounts of calcium and magnesium. Admittedly, grazing results in the subsequent re-deposition of nutrients – but the nutrients usually are not well distributed across the field.

Weeds are another reason to pay attention to the pH of the soil. Whenever soil pH is out of the optimum range for forages, certain weedy species may become more prevalent because they are more tolerant of soil acidity (or alkalinity) than the desired forages. Under these conditions, certain indicator weedy plants may give an early warning that soil pH needs to be adjusted (see OH 81 Using Plants as “Indicators” for Diagnosing Turf Problems by Sid Bosworth, University of Vermont Extension Agronomist).

In the absence of additional limestone as a routine maintenance practice, the soil pH starts trending down after a few years due to the processes discussed above. Then the weeds that can tolerate lower soil pH start to take over.

How Much Lime is Needed?

The desirable pH range for our forage legumes is 6.8 -7.0. A pH above 6.0 is satisfactory for grasses. Because a mixed stand of both makes desirable hay or pasture, the goal is to lime to the need of the more sensitive legume crop (6.8-7.0).

The amount of limestone necessary to obtain the desired pH varies with soil texture, organic matter content, and previous liming practice. A soil nutrient analysis, conducted on soil samples collected before limestone and fertilizer are applied, is the best guide to determine the quantity of ground limestone needed to adjust the soil pH into the optimum range for crop production. Adjusting the soil to an optimum pH is especially critical before establishing a new seeding because high soil acidity (low soil pH) can impair seedling development resulting in reduced or failed stands.

Once soil acidity has been corrected, one ton of ground limestone should be applied per acre every two to three years to maintain soil pH at that same level.

Placement of Limestone

Limestone moves downward only about an inch per year in most of our Connecticut soils. Therefore, the amount of limestone applied, the placement of the limestone, and the type of tillage used control how fast soil acidity is corrected. For hay and pasture stands that are to be improved without plowing and reseeding, limestone is topdressed at one to two tons per acre according to soil test. When more than two tons are needed, another one or two tons is then broadcast a year later followed by a ton per acre every three years thereafter.

Where hay or pasture crops are to be seeded, it is recommended that the required limestone, up to 2 tons per acre, be applied after plowing and harrowed in by using a disk. This practice provides optimum correction of acidity in the root zone of the establishing seedlings. If heavy application rates are required, plowing under a part of the limestone and disking in the remainder after plowing is the most desirable way to correct soil acidity.

Uniform spreading of limestone is essential because little lateral movement of limestone occurs in the soil.

When to Apply Limestone

Maintenance applications of limestone may be applied at any time of the year that soil conditions are suitable to bear the weight of the spreading equipment. Limestone could be applied to frozen ground that is free of snow although it is preferable to apply to unfrozen ground. Applications to the surface of snow should be avoided, because the likelihood of loss during runoff in the spring is higher.

With our most acid-sensitive forage crop, alfalfa, the timing of limestone application before planting can be critical. Limestone is slowly soluble in the soil, and several months to a year may be needed to raise the pH high enough for the alfalfa to establish and grow well. Other legumes are less sensitive, but the greater the progress in correcting acidity, the easier the establishment of the new crop, the faster it becomes a productive stand and the less weed pressure you will have.

Legumes are much more deeply rooted than grasses. Therefore legumes need to have the pH adjusted to a deeper depth. Since legume roots penetrate deeper than the traditional plow depth, additional time may be needed in fields with an extremely low pH to allow the limestone to move below the plow layer into deeper soil layers to increase the pH of the deeper soil, which often has a pH of 4.5 to 4.8. This phenomenon is most clearly seen in newly cleared forest lands. Legume stands in these fields usually do not last 5 or more years, which is typical in better soils. The short duration of legume stands on newly cleared land is due to the inability of the roots of the legumes to grow into the lower soil depths because of the low pH in the lower depths. The shallow rooting depth reduces nutrient and water uptake and stresses the plants, which reduces the longevity of the stand. Legumes also have a symbiotic relationship with mycorrhizial bacteria that live in the root nodules and fix nitrogen. The growth of these bacteria is inhibited by low soil pH and their declining populations further weakens legumes being grown in low pH soils.

In soils that have recently been cleared, it is beneficial to grow more acid tolerant plants for a few years while applications of limestone and the passing of time can work together to reduce the soil acidity in the deeper soil depths to a level that will allow a legume crop to succeed.

What Kind of Limestone Should be Used?

Ground limestone, commonly known as agricultural limestone is the most readily available and economical liming material. Historically there are records that refer to the use of “burned or quick” lime and hydrated lime during various time periods. Quicklime is made by heating limestone (CaCO3) in an oven or kiln and creating CaO. This type of lime is still made but the cost prohibits its use in general agricultural practice. Hydrated lime (Ca(OH)2), sometimes referred to as “slaked” or pickling” lime, is formed by mixing or “slaking” quicklime with water, resulting in a more expensive product that is extremely reactive and caustic. The cost generally restricts its use to specialty applications.

The agricultural limestone produced in Connecticut is dolomitic limestone that contains higher levels of magnesium than calcitic limestone that is mined in other parts of the country. This magnesium is desirable for the production of forage crops because both the plants and the animals need magnesium. Since it already is a component of the limestone, one does not need to purchase magnesium separately as is necessary for some areas of the country.

Agricultural limestone (aglime) is marketed in two forms, powdered or pelleted. Pelletizing adds an additional cost to the limestone, which is usually not warranted for agricultural use. That said, however, there is a relatively large market for pelletized limestone in the landscape industry. The pelletizing process involves mixing regular ground aglime with some type of binder that serves to hold the limestone together. This process eliminates the dust, allowing the limestone to be applied with standard rotary fertilizer spreading equipment and making the use of limestone in a residential area easier and cleaner. Typical agricultural lime is ground limestone with varying degrees of fineness depending on the use and the application equipment. More finely ground limestone reacts more quickly in the soil to reduce acidity – but it costs more and the application creates more dust.

Farmers usually have their limestone applied by a custom applicator because aglime is dusty, used at high rates, and requires the use of specialized equipment. These commercial applicators usually have rotary spreaders that spin the limestone onto the field in 20 to 40-feet wide swathes. Limestone used by these trucks is usually more coarsely ground to reduce the cloud of dust associated with this high powered equipment. Due to the large size of this equipment it is unable to be used in small fields. In these cases there are spreaders available usually 3 to 8-feet wide that can be towed behind small tractors or even ATVs to spread smaller fields by dropping the lime directly onto the soil surface. These spreaders are priced in the one to three thousand dollar range but can be worth the investment due to the continual need to apply limestone over the years.

Liquid or fluid lime is an aglime suspension in water. This form of lime is a relatively new product. Liquid lime permits more uniform application and eliminates the dust problems of spreading dry forms of limestone. To achieve suspension, the aglime is very finely ground; hence it reacts slightly faster than most dry forms to correct acidity. This type of lime is not used by farmers, but the landscape industry has adopted its use almost exclusively. Hydro seeding of limestone, seed, fertilizer and mulch in one application is now standard practice.

Fertilizers

Soil fertility largely determines the forage crop yield that can be achieved. If soils are deficient in nutrients, only small crop yields will be realized. The goal of any fertilization program is to produce the maximum economic yield for the crop whether harvested as hay, haylage, or as pasture. A fertility program based on the soil nutrient analysis is the best guide to the amounts of fertilizer or manure to apply.

Table 1, Nutrient Value of Fertilizers, lists the fertilizers commonly available in Connecticut and the amount of nitrogen (N), phosphorus (P2O5) and potassium (K2O) provided. The values on the soil test report are in pounds per acre. Fertilizer bag labels list percentages. To calculate how much fertilizer is needed to provide a given nutrient, divide the pounds per acre number by the percent on the bag (as a decimal). The result will be the pounds of fertilizer to apply per acre to obtain the needed nutrient.

Table 1. Nutrient Value of Fertilizers (Guaranteed analysis -percent by dry weight)

Fertilizer	N (%)	P₂O₅ (%)	K₂O (%)
Ammonium Polyphosphate	10	34	0
Ammonium Sulfate	21	0	0
Ammonium Nitrate	34	0	0
Diammonium Phosphate	20	50	0
Monoammonium Phosphate	12	50	0
Muriate of Potash	0	0	61
Potassium Hydroxide	0	0	70
Potassium Nitrate	13	0	45
Potassium Sulfate	0	0	50
Sulfate of Potash Magnesia (Sul-Po-Mag)	0	0	22
Triple Superphosphate	0	46	0
Urea	46	0	0

When to Fertilize

Fertilizers, by definition, are natural or synthetic substances that supply nutrients to plants. Therefore, it makes sense to apply fertilizers when the plant is actively growing so it can use the nutrients to support its growth and development. In Connecticut, the growing season is traditionally considered to be May through October. In some years the season may extend earlier into April or later into November or December but even when it does, not many nutrients are taken up during these periods. Ideally plant nutrients should be available when the plants can use them most effectively. Because it is difficult to predict this exact moment, we tend to fertilize early and let the plant absorb nutrients at its own pace. Unfortunately, this introduces some inefficiencies and the potential for nutrient losses.

Established Stands

Maintenance applications of fertilizer phosphorus (P2O5) or potassium (K2O) can be made at any time during the growing season with little risk of loss to the environment. Nutrients applied late in the season will not be available to support crop yields in the year of application, but the fertilizer will stay in the soil through the winter and be there for uptake during the next growing season. Nitrogen (N), on the other hand, is different. Nitrogen is both volatile and soluble, and requires special consideration.

Urea is the most common form of nitrogen fertilizer available in Connecticut and it is highly soluble in water. Once in solution, the urease enzyme hydrolyzes the urea, breaking it down into ammonia and carbon dioxide. The ammonia can then dissipate into the air and be lost. This process is known as volatilization. Volatilization can cause the loss of up to 60% of the N applied as urea or as ammonium forms of N. The conditions that increase the chance of losing N to volatilization are application to the soil surface, rainfall or dew sufficient to dissolve the fertilizer granules but not sufficient to wash into the soil, plant material on the soil surface, and windy or humid conditions. Because N is usually applied to the soil surface of hay and pasture crops, it is best to apply urea and ammonium fertilizers before a prediction of at least a half inch of rainfall. This amount of rainfall is sufficient to wash the fertilizer into the soil where the ammonia gas produced will be captured by the water in the soil pores instead of lost to the atmosphere.

Some forms of nitrogen are very soluble and will readily dissolve in water. As the water flows down through the soil profile, it can carry, or leach, the nitrogen through and out of the root zone. Once out of the plants root zone, the nutrient is unavailable for plant uptake. The nitrogen may enter and contaminate ground water supplies and can also make its way into nearby surface waters resulting in eutrophication, which is the undesired stimulation of vegetative growth in lakes, ponds and other water sources.

Nitrogen fertilizer, therefore, should be applied to minimize volatilization and leaching losses. Too much rainfall can leach N from the soil, but too little rainfall immediately after application can cause large volatilization losses of N. Because no one can accurately predict the weather, it is recommended that nitrogen fertilizer be applied to fields in smaller amounts at several times during the growing season. For grass (legumes do not need N fertilizer due to the nitrogen-fixing bacteria) divide the annual maintenance amount of nitrogen needed (100 lbs per acre) by the number of cuttings obtained in a normal year, and then apply this amount during stages of active growth. For example, a grower that normally harvests 3 cuttings a year should apply about 33 pounds of nitrogen per acre, 3 times per year. The first as early in the spring as it is possible to get equipment into the field without damaging the grass, and then immediately following the first and second cuttings. This schedule minimizes the losses due to leaching because the plants are actively growing and needs the nutrients. Volatilization losses are also minimized because the amount of fertilizer per application is lower, and chances are that conditions will not be favorable for losses at all of the applications.

New Seedings

For new seedings, apply suggested fertilizers after plowing and incorporate fertilizers, along with any recommended limestone by disk-harrowing. For operations with smaller equipment, attempting to spread across freshly plowed fields can be a challenge. In this case, a light disk harrowing might be needed to create a smoother driving surface prior to fertilizer application. Most fertilizer dealers will arrange for custom application whether fertilizers are applied at seedbed preparation or as topdressing.

Manure

Manure can be beneficial for crop production in multiple ways. First and foremost, the manure contains nutrients. The amount of nutrients in manure varies depending on: the species of livestock; whether the manure is handled as a liquid or a solid; how much bedding is mixed in with the manure; and how the manure is handled and stored. Manure adds organic matter to the soil which increases the water holding capacity of the soil, increases the air space in the soil – making it easier for water to infiltrate. It also adds micronutrients to the soil. Micronutrients are nutrients that plants need, but in very small quantities. While these nutrients are essential, they are also very expensive, so it makes good economic sense to apply manure at least every few years to provide these nutrients.

Timing and application of manure is basically the same as nitrogen fertilizer. Because manure contains nitrogen, one needs to take the same precautions with manure as with nitrogen fertilizers to prevent both volatilization and leaching of nutrients. Manure is a little more environmentally risky to apply compared to nitrogen fertilizer because the manure also contains soluble forms of phosphorus. This soluble phosphorus can move with water through the soil and also can be lost by surface erosion of soil particles. Like nitrogen, it can cause the degradation of water resources by promoting algae blooms and eutrophication in fresh water systems.

Due to the variation in the nutrient content of manure discussed above, it is recommended that specific manures be analyzed for nutrient content, but even a manure analysis will provide only a rough estimate of the nutrient content of manure because of the difficulty of obtaining a sample that accurately represents the nutrient concentration of the manure. A number of laboratories in the Northeast will analyze the nutrient content of manure for a small charge.

Table 2. Nutrient credits for various types of manures.

Manure	N	P₂O₅	K₂O
Beef	11	9	10
Dairy (solid)	5	3	6
Goat	8	10	2
Horse	12	4	9
Poultry (solid)	16	20	12
Sheep	11	8	19
Swine	14	11	11

Crop Nutrient Needs

Anyone involved in growing a crop asks the same question “How much fertilizer or manure should I apply to a given crop?” Unfortunately, the answer is “It depends!” It depends on a number of factors: the crop, the fertility level already in the soil, the yield goal desired, the soil temperature, rainfall and other factors too numerous to mention. The best way to estimate nutrient needs is to have the soil analyzed for the availability of nutrients. The University of Connecticut Soil Nutrient Analysis Laboratory will analyze the soil for a small fee and provide a fertilizer recommendation based on the crop desired.

If time constraints or other circumstances are such that you are unable to analyze your soil before applying fertilizer or manure you may refer to Table 3. Maintenance Fertilizer Recommendations for Perennial Crops, or Table 4. Fertilizer Recommendations for Seeding an Annual or Perennial Crop for generic recommendations as appropriate to your needs.

Table 3. Maintenance Fertilizer Recommendations for Perennial Crops

Crop	N (lbs/acre)	P₂O₅ (lbs/acre)	K₂O (lbs/acre)
Alfalfa	0	48	214
Alfalfa, Grass Mix	0	13	71
Clover, Alsike	0	33	154
Clover, Crimson	0	33	154
Clover, Grass Mix	0	13	71
Clover, Ladino	0	33	154
Clover, Red	0	33	154
Grass	100	23	31
Orchardgrass	100	23	31
Pasture, Grass	100	34	31
Pasture, Legume & Grass Mix	0	13	71
Reed Canarygrass	100	23	31
Rye, Cereal	40	34	0
Ryegrass	100	23	31
Ryegrass, Tetraploid	100	23	31
Tall Fescue	100	23	31
Timothy	100	23	31
Trefoil	0	33	154
Trefoil, Birdsfoot	0	33	154
Trefoil, Grass Mix	0	13	71

Table 4. Fertilizer Recommendations for Seeding Forage Crops

Crop	N (lbs/acre)	P₂O₅ (lbs/acre)	K₂O (lbs/acre)
Alfalfa	40	78	49
Alfalfa, Grass Mix	40	78	49
Barley	40	27	19
Buckwheat	30	20	45
Clover, Alsike	40	78	49
Clover, Crimson	40	78	49
Clover, Grass Mix	40	78	49
Clover, Ladino	40	78	49
Clover, Red	40	78	49
Corn, BMR	140	46	72
Corn, Field	140	46	72
Grass	40	44	0
Kale	160	130	125
Oats	40	27	19
Orchardgrass	40	34	0
Pasture, Grass	40	44	0
Pasture, Legume/Grass	40	78	49
Reed Canarygrass	40	27	19
Rye	40	34	0
Ryegrass	40	23	31
Ryegrass, Tetraploid	40	34	31
Small Grains	40	27	19
Sorghum	100	39	49
Sorghum/Sudan Grass	100	39	49
Soybeans	40	27	19
Sunflower	80	25	50
Tall Fescue	40	34	0
Timothy	40	34	0
Trefoil	40	64	29
Trefoil, Birdsfoot	40	101	9
Trefoil, Grass Mix	40	101	9
Triticale	40	27	24
Turnip	50	50	50
Wheat	40	27	19

W.W. Washko and G.F. Griffin. 1982. University of Connecticut Cooperative Extension System. Revised By R.A. Meinert, T.F. Morris and D. Pettinelli. 2011. University of Connecticut, Departments of Extension and Plant Science & Landscape Architecture, College of Agriculture and Natural Resources.