Sustainable Landscaping
healthy lawn care
rain gardens



A lawn that is healthy and well-established can out-compete most weeds and withstand a certain amount of stress from drought, insects, and disease.

Lawns can often be renovated simply by improving management such as proper fertilization, mowing, watering, and addressing problems with thatch and soil compaction.

URI Cooperative Extension Botanical Gardens - an attractive, healthy lawn requiring minimal fertilizer, pesticides and water.

Here are some healthy lawn care tips:

Fertilization Guidelines
Soil Testing Labs
University of Connecticut soil testing lab
University of Massachusetts soil testing lab
Proper Application Methods
Soil Compaction, Thatch and Mowing
Additional Resources

Fertilization Guidelines - view reference

If a lawn is unfertilized and is considered acceptable, then do not fertilize.

If the lawn is considered unacceptable, assess why ( pests, compaction, shade, low fertility, etc. ). If fertilization is needed, consider these fertilization guidelines:

Recommendations for Managing Nitrogen ( N ) on Lawns

Recommendations for Managing Phosphorus ( P ) on Lawns

Other N and P Management Considerations

Recommendations for Managing Nitrogen ( N ) on Lawns

Do not apply before spring green-up and apply no later than October 15th. Avoid mid-summer fertilizing.

Apply one-half to one-third (or less) of that recommended on the fertilizer bag label and then monitor lawn response. Reapply at the reduced rate only when lawn response starts to fall below acceptability.

Slow-release formulations are preferable to soluble, fast- release formulations.

Apply a maximum of 2 lbs. N / 1000 sq. ft. / year on an established lawn 10 years old or older. Newly seeded turf, especially on new home sites where the topsoil has been removed, may require more.

If a soil test indicates phosphorus (P) and / or potassium (K) are adequate, then fertilize with only nitrogen (N). If only blended fertilizers are available, choose the one with the lowest P content.

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Recommendations for Managing Phosphorus ( P ) on Lawns

Always test the soil to determine phosphorus levels before applying. Soil test annually for P when applying organic fertilizers derived from composts to ensure that P levels do not become excessive.

If phosphorus fertilizer is required:

Avoid using P fertilizers on bare ground or on low-density lawns, unless it is a new seeding.

Use P-free fertilizer on established lawns, unless soil tests indicate P is too low.

Avoid applying phosphorus fertilizers when moderate to heavy rain is in the forecast.

Never apply phosphorus fertilizers to saturated or frozen ground.

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Other N and P Management Considerations:

Return clippings and mow as high as possible (leave at least 3 inches). Clippings can supply slow-release nitrogen to the lawn and allow for reduced fertilizer applications. On a well-established lawn, this can often supply adequate P and K for the lawn.

Choose grasses, such as fescues, that require less water and nutrient inputs.

Maintain a soil pH of 6.0 to 7.0. This will ensure that most of the nutrients necessary for good turfgrass growth will be available to the grass plants. Monitor pH levels to determine if liming is necessary or not.

Consider seeding white clover or other legumes into the lawn to naturally provide nitrogen. View our Davisville Demonstration Site.

If supplemental watering is applied, avoid overwatering. Do not exceed a total of 1 - 1 ½ inches of water per week, including rainfall amounts. Water wisely.

Leave a buffer strip of at least 25 feet of unfertilized grasses or other vegetation around water bodies (streams, rivers, lakes, estuaries, bays, coastal areas, vernal pools, wetlands, or drainage areas).

Avoid using combination products that include both fertilizer and weed killers as the application rates of such products are based on the weed killer rather than the fertilizer. Pesticides should not be applied within 25 feet of surface water.

When establishing a new lawn, organic matter content should range from 3% to preferably 5%. Incorporate compost or another organic material into the soil to raise the organic matter content as needed.

The information contained within these lawn fertilization guidelines is adapted from: Guillard, K. 2008. New England Regional Nitrogen and Phosphorus Fertilizer and Associated Management Practice Recommendations for Lawns Based on Water Quality Considerations. University of Connecticut.

This material is based in part upon work supported by the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture, under agreement number 2006-51130-03956.

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Proper application methods

It is very important to measure the actual area to be treated with fertilizers and/or pesticides and to calibrate your spreader. This ensures that you are applying the amount of product that you intend.

Avoid spreading fertilizer on paved areas or near storm drains or drinking water wells. Sweep up these areas with a broom, do not wash with a hose.

A drop spreader can allow for more accurate control around critical areas.

Compost and other organic fertilizers are still sources of nutrients, so they must be applied at the proper rate and time using sound application methods.

The same applies when applying a pest control product. Avoid weed and feed products and routine pesticide applications. Nutrients should be applied based on soil test results and managed separately from pest management. Use the following Integrated Pest Management techniques:

View our page on alternative white grub control as an example:

  • Properly identify the pest problem.
  • Is the problem bad enough to warrant chemical treatment?
  • Learn about the pest -- identify cultural, mechanical, biological options for controlling the problem.
  • If chemical control is necessary, is spot treatment an option or is uniform application needed?
  • Are there chemical control options that are less toxic and / or occur in a less risky formulation (granular instead of spray)?
  • Be sure that the pest problem is not self-induced due to improper fertilization, watering and mowing practices--these can cause shallow roots, disease and other lawn health problems.
  • Choose the right lawn grasses. View our Davisville Demonstration Site.

URI Plant Protection Clinic: (401) 874-2900
Assistance with identification of plant insects and disease

Grass clippings are a pollutant when washed directly into surface waters and storm drains. Recycle grass clippings on the lawn, compost them in a safe place away from water resources, or use them as mulch in beds. View our page, Recycle your yard waste, for more information.

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Soil Compaction, Thatch and Mowing

Soil compaction and thatch build-up result in shallow roots and reduced water infiltration and air flow. Mechanical soil aeration, vertical mowing (thatch removal) and coring can help loosen compacted soil. It is not unusual for residential lawns to contain shallow top soil and compaction from frequent vehicle access and foot and animal traffic.

Thatch is a dense layer of dead grass, stems and roots that develops between the soil surface and the growing grass. While some thatch is normal and desired, excessive thatch problems are often a sign of over-watering and improper mowing. Mechanical de-thatching in the early fall is recommended for lawns with more than one inch of thatch build-up.

Proper mowing at the correct heights and frequencies with a sharp blade is very important for lawn health. Mowing at heights between 2 and 3 inches is best to encourage deeper roots, discourage weeds and reduce evaporation.

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Additional Resources

University of Connecticut Cooperative Extension Water Quality and the Home Landscape
Sustainable Landscaping: Turf Management Page

URI Master Gardener Hotline at 1-800-448-1011

URI Plant Protection Clinic: (401) 874-2900
Assistance with identification of plant insects and disease

Soil Testing Labs
University of Connecticut soil testing lab
University of Massachusetts soil testing lab

Nutrient Management Guidelines for Turfgrass Sod Production in Southern New England

Davisville Demonstration Site -- lawn renovation with shade tolerant grass mix and white clover.

Davisville Demonstration Site -- alternative white grub control