ASK THE MASTER GARDENERS
Q: I’ve been putting chemicals on my lawn for years and now I want to stop. Can you give me some advice on how to go organic?Will my lawn look awful for a few years?
A: Your question is a common inquiry as more and more residents want to cultivate their lawns without chemicals. This usually means managing pests without traditional pesticides. A visit to any lawn that is maintained in this way could answer your aesthetic concerns as examples are all around us. Many residential properties and public spaces have been maintained without pesticides for years, and they look great.
The first question to ask when considering a transition away from the use of traditional pesticides is what level of aesthetic appearance you find acceptable. Are you looking for “lawn perfection,” with little tolerance for weed growth or damage from disease or insect activity? Are you looking to prevent or quickly terminate such problems if they do occur? If some weed growth is acceptable and occasional insect infestations and disease flare-ups are allowed as a natural possibility, then the transition to a lawn free of traditional pesticides will be easier.
Because you can’t take away traditional pesticide management and substitute an environmentally friendly management method for every problem that may occur (like trading one pill for another), practicing lawn care in this way means the acceptance of a different philosophy of lawn care. The latter largely employs cultural methods that improve the general heath of your turf, enabling it to withstand occasional pest onslaughts rather than using chemicals to try to maintain perfection. Once you’ve accepted this new philosophy, you may want to employ the following steps toward removing traditional pesticides from your lawn care program:
Organic matter counts! This means using compost, either incorporated generously before seeding a new lawn or after core aerification on an existing lawn. Regarding the latter, remove the cores and work the compost down into the holes each September for several years.
Buy a mulching mower. Work autumn leaves and grass clippings back into your lawn. This will benefit your turf and the environment.
Raise your mowing height to 3.5 to 4 inches. More height means longer roots, increased drought resistance and more root material to compete with attacks by root feeding insects. It also means vigorous, taller grass plants that can more easily crowd out or compete with weeds.
Water your lawn. Lawns allowed to go dormant may survive and grow again, but weeds such as clover and crabgrass will gain an advantage. In most instances, experts suggest 1 inch of water per week (inclusive of rainfall) for lawns in the Northeast. This may be applied all at once during the cooler spring and fall, but is best applied in one-half to one-third inch amounts two to three times per week in the heat of summer. That’s when grass roots deteriorate and deep watering serves little purpose.
Calibrate the output of your sprinkler. Place straight-sided containers within the spray pattern to see how much water your sprinkler delivers in a half hour. This makes it easy to follow suggested guidelines and avoid overwatering, which can cause or worsen disease outbreaks. Reduce the time grass leaves are wet. Do this by watering between 4 and 7 a.m. (the time of natural dew formation). If this schedule isn’t possible, water so that the grass will be dry before nightfall. Never water grass at night.
Consider fertilizing your lawn. Several university turf experts have concluded that a properly fertilized lawn (not an over-fertilized lawn!) may be more dense and may actually benefit the environment more than lawns that are never fertilized.
Reduce the size of your lawn. Create beds of low-maintenance groundcovers where lawn is not essential. This can reduce the need for mowing, watering and fertilizing.
If pest problems occur, don’t panic. Grass seed is relatively inexpensive and autumn comes every year. You can usually fix the problem then.
For Cornell University fertilizer guidelines that reflect current fertilizer laws and information on leaf mulching and grasscycling, contact your local Cooperative Extension or visit your local CUCE website.
Gerald Giordano, Senior Horticulture Consultant/Cooperative Extension Agent, Cornell Cooperative Extension of Westchester County
Addendum from Jerry:
There is a bit of a debate among turf experts about core aerification. Dr. Frank Rossi and Dr. Marty Petrovic on campus think it is only useful in the short term…but useless beyond that. Dr. Tamson Yeh at the Cornell research center on Long Island thinks it works in the long term as long as cores are removed and you get compost down into the holes.