Healthy Environment, Strong Communities, Accountable Government


When maintaining a lawn organically, it is important to focus on the health of the plants and the soil. Prevention is more important than quick fixes. Weeds, insects, and turf diseases are symptoms of an underlying problem with the soil - malnutrition. Here are steps you can take to have a healthy, attractive lawn without either toxic
pesticides or synthetic fertilizers.


*       Set mower blades at 3 inches. Cutting grass higher shades weed seeds and keeps them from growing. Mow regularly; never cut off more than 1/3 of the grass blade at once, otherwise the grass will be stressed and more susceptible to disease. Keep your lawn at 3 inches,
and cut when it reaches 4 inches. This may require midweek mowing during the fastest growth periods. Leave grass clippings on the lawn as mulch. In healthy, organic soil they break down quickly. This will return nutrients and organic matter to the soil, reducing the need for fertilization and watering.
*       The last mowing of the season in fall should be short, to prevent winter damage.

Test Your Soil

*       Check the pH balance of your soil. Soil test kits and pH meters are available commercially at garden supply stores. Keep your soil as close to 6.5 as possible. Long Island soil is likely to be more acidic (less than 6.5).
*       You can also test your soil for mineral, nutrient, and organic matter content. Private testing labs can do this, as well as the Cornell Cooperative Extension (Nassau 454-0900, Suffolk 727-7850).


*       Compost has been called: "the magic soil," it can be put down any time of the year. When applying compost: spread it 1/4 to 1/2 inch thick, then rake it into the turf. Compost is especially important if chemicals have been used on the lawn. It will re-establish important micro-organisms that the pesticides and synthetic fertilizers kill. Compost can be acquired at municipal composting facilities. (See page 19.) Compost made by homeowners is usually not well balanced enough for use on lawns. Homemade compost may be used in gardens. Compost will reduce the need for fertilization, aeration, and lime.
*       Liquid compost and compost tea can be easily applied with a sprayer, and have most of the benefits of compost.

*       Compost should also be spread under trees and shrubs to prevent insect infestations. Remember these are indicators of stress in the plant, usually due to inadequate nutrition in the soil.


*       If your soil has a pH of less than 6.5 it is too acidic, add lime to raise the pH. Lime also adds calcium to the soil discouraging dandelions. Turn lime 2" deep into the soil before establishing a new lawn for optimum root growth, although this is not practical for established lawns. Look for pelletized lime, it is more effective and
easy to apply.
*       Applying a quarter dose of lime 4 times through the season will prevent swings in your soil's pH.

Rock Dust

*       Rock dust adds trace minerals that are important for plant growth. This can be spread any time of year, even in the winter. The first year, apply 4 bags per acre, the second year only half as much will be needed.


*       Fertilizer is much less important with organic lawns than it is with chemically-dependent lawns. The excessive, quick release nitrogen found in synthetic fertilizers cause growth spurts which weaken the grass plant and increase the risk of disease. If your soil
is very low in nitrogen, consider an organic fertilizer.
*       Although organic fertilizer can be applied at any time of year without fear of burning your lawn, the fall is the best time. Always wait one week after applying lime, before fertilizing. Choose an organic fertilizer with low water soluble nitrogen. The amount of water soluble nitrogen should be listed on the back of the bag (7% or
less is good). Organic fertilizers will have much lower N-P-K numbers than synthetic fertilizers.
*       Rock phosphate (4% water soluble phosphorus, 32% total phosphate) will add phosphorus which is important for root systems and should be added in the fall.


*       Water deeply. You should wet the soil down to the full depth of the root zone, 6 to 18 inches. In the sandy soils of Long Island, that means applying about one to two inches of water. If you don't know the precipitation rate of your sprinkler you can determine it by placing a coffee can within its range and measuring the depth of
water collected in the can after an hour. Do not water in the middle of the day, when evaporation loss is greater.
*       Proper watering is very important. More lasting damage can be done to a lawn by improper irrigation than by drought. Healthy soil with sufficient organic matter will do more to help your lawn through summer than an irrigation system. Soils that have been sterilized by chemical application and have little soil life and organic matter are much more susceptible to drought and "browning out." Drought resistant grasses such as fescues will also reduce the need for watering.
*       A healthy lawn will not die of thirst in Long Island's
climate, but it may go dormant and turn brown in the height of summer. Water only when necessary. Some experts advise watering only when grass begins to wilt. The grass will turn a dull, grayish color, and will not spring back, leaving footprints after you walk over it.
*       Do not water too early in the season, and do not water frequently and lightly. Light, early watering encourages shallow root growth. These shallow roots will dry out quickly in dry hot weather.

*       Do not over-water. Yes, it is possible to over-water, soil saturated with water will deprive the roots of oxygen, suffocating the turf. Overly wet conditions can also encourage disease.
*       Be aware of local restrictions. Nassau County prohibits watering between 10 am and 4 pm, and allows watering only every other day. Houses with odd street numbers may water only on odd numbered days, and even numbered houses only on even days.

Autumn Raking

*       Let autumn leaves remain around shallow rooted plants such as maples, azaleas, and rhododendrons. Removing leaves will slowly starve these plants. Leaves also keep roots from drying out and prevent winter burn.

Aeration and Thatching

*       Lawns with ample organic matter, that do not get heavy traffic should never need aeration. Microbes and earthworms keep the soil from becoming compacted. If you have a high traffic area were soil becomes compacted even after organic matter has been
established, consider core aeration. Core aerators, which remove small plugs of soil to increase air circulation to roots and decrease compaction, can be rented. It is best not to aerate in the spring, because it may bring up weed seeds that are more likely to germinate and grow in the spring. If you do core aeration in the spring, follow it with a top-dressing of compost, and overseed to cover and crowd out any weed seeds. The best time to do this is between April 15 and
May 15, before crabgrass begins to germinate.
*       Most organically maintained lawns will not have a problem with thatch because the organisms in healthy soil break down the thatch. If you have a thatch problem, a light top-dressing of compost, or Ringer Lawn Restore, will add micro-organisms that break down thatch.

If You Have a Weed or Pest Breakout

*       Do not use chemical pesticides (including insecticides, weed killers, and fungicides) or synthetic fertilizers, these will kill the beneficial organisms in the soil, and undo the benefits of any previous organic care.
*       Weeds can take hold in bare or thin patches. Overseed where grass is thin or stressed. A fescue blend of grass seed is suggested as best for Long Island, as fescue has deep roots and is drought and
acid tolerant. It also creates a thick mat which resists weeds.
*       Small outbreaks of weeds can be weeded by hand or killed with hot water. Cover larger patches of annual weeds with a mixture of lime and compost then overseed. For lawns with wide-spread weed
infestations, corn gluten applied early in the spring will offer significant control. Corn gluten can be expensive, use it only where you have a tough weed problem. Timing is important, the best time to apply corn gluten for crabgrass control is right when the flowers of forsythia bushes first open. Never apply corn gluten when you are
seeding, it will prevent the grass seed from growing.
*       Fleas, ticks, mosquitoes, and most other pest insects can be repelled with garlic oil. You can buy garlic oil concentrate in lawn and garden stores. Or, to make your own, crush a handful of garlic cloves and soak them in a gallon of water for a day. Strain out the garlic before putting the water in a sprayer. Spray around your
property. Do not spray flowering plant, or bees will not pollinate them. If you are having a barbecue or outdoor party, spray a few days before, the garlic will have a strong odor until it dries (about a day). Garlic can keep pest insects off your property for three to four weeks.
*       Hot pepper wax, available in lawn and garden stores will repel insects from your bushes, flowers, and vegetables.
*       Remember weeds, insects, and diseases are indicators of an underlying condition. If you only treat the symptom and not the cause, they will recur. The underlying cause is usually malnutrition of the soil and the plant. Remember to feed the soil.

Thank you to Steve Restmeyer of Eco-Logical Organic Landscaping (345-6040) and Jeff Frank of the Lyceum (288-2834) for helping with this article.

Neighborhood Network
7180 Republic Airport, East Farmingdale, NY 11735 Tel: (631) 963-5454
Advocates for Long Island's Environment