Friday, May 28, 2004
We all know that synthetic pesticides and herbicides on our lawns can be harmful to bugs, fungi, and other living things (like us). But it's so easy to succumb to the lure of the easy green lawn, to believe that the stuff on our lawns won't get into our families' bloodstreams or seep into a well or into other creatures' food chains.
I admit I was a weed-and-feed junky. I also admit that in the four years or so since I kicked the chemical habit, my lawn has gone from pretty to pitiful. By midsummer last year crabgrass had overtaken nearly half my lawn. By fall, when the crabgrass died back, it was scorched earth out there. The fall rains turned everything to mud, pounds of which came in on the dog's paws.
We had used "natural" fertilizers and corn gluten to deter weeds. I put down milky spore one year to get at the Japanese beetle grubs, and last year I tried beneficial nematodes. It seemed I did everything at the wrong time, in the wrong way. I was hopeless.
This year, I have something better than hope — I have a plan. At the organic lawn-care seminar in town recently, Pat Beckett and Chip Osborne from the Living Lawn project in Marblehead, cleared up a lot of the confusion for me. The bottom-line message from the seminar was this: initially, it takes more time and effort, and maybe more expense, to bring your lawn to nature, but in a year or two, your lawn could be as pretty and certainly healthier and more resilient than it was when it depended on synthetic feeds. Just as there are steps to the commercial fertilizer regimens, there is a method to organic lawn care. The amount of work you put into it depends on whether you crave an all-grass "monoculture" or whether you can tolerate (maybe even love) a few dandelions and clover.
To transition from chemicals, you need to restore organic matter to your soil. Basically, a commercial weed-and-feed program is a take-no-prisoners approach — it kills beneficial organisms along with the grubs and bugs you don't want. Lawns get hooked on the synthetic fertilizers. When you stop using them, your soil lacks the nutrients and microbes grass needs to thrive; unfortunately, the weeds do just fine. You can throw down natural fertilizer and corn gluten till the cows come home, but you're not going to have much for them to munch until you make it a happy home for grass.
Compost is a key to a healthy lawn. By spreading a quarter- to a half-inch over a lawn, you contribute a host of organisms and nutrients. Compost even helps to break down the accumulated thatch of dead roots, eliminating the need for mechanical dethatching. The compost top dressing disappears fairly quickly so you won't look at brown for long. Osborne said two or three applications may be best when you're just making the transition, but in an established organic lawn, one application of compost in the fall is enough. You need well-aged compost.
Aerating is another key. Soils compact with weather and traffic, so it's important to loosen the soil in the spring. Aerating allows grass to develop deep roots, and this makes the lawn more drought-tolerant. The aerating process itself kills grubs.
Spreading the compost is pretty labor-intensive with shovel and rake. A typical lawn spreader will work, but only if the compost is very dry. Mechanical compost spreaders are just beginning to come on the market. If enough of us ask, maybe our lawn services will offer compost spreading. The more of us who want to go organic, the more they'll want to learn about how to provide the right services.
The Living Lawn project in Marblehead has yielded a wealth of other information:
• Weed control: Corn gluten used consistently is a good pre-emergent herbicide, but don't put it down when you've planted grass seed.
• Liming: Test the soil to find out whether you need lime and what type — calcitic if you need more calcium than magnesium, dolomitic in the unusual case that your magnesium need is greater. If your lawn happens to be too alkaline, use gardener's sulfur.
• Fertilizing: Use natural slow-release products; avoid water-soluble and high-nitrogen fertilizers because they tend to run off.
• Watering: It's better to water deeply a couple of times a week than to water a little several times; water more frequently to get seed started.
• Mowing: Don't overdo it; keep the mower blades sharp and keep the grass to three or four inches. Longer grass shades out the crabgrass! Leave the clippings — they're nutritious, and they are not thatch.
You can plant a "nurse crop" of fast-growing annual rye to get a jump on weeds. I'm trying this in my crabgrass garden now; it's touch and go whether I've done it in time.
"The Living Lawn experts came to town on April 27 at the invitation of the Carlisle Pesticide Awareness Group (CPAG), in association with the Board of Health and the Carlisle Conservation Commission. For more information about CPAG and its work in Carlisle, contact Chris Chin, email@example.com."
The Living Lawn booklet made available at the seminar explains the whole program in a lightweight 22 pages. You can obtain a copy of the booklet by e-mailing firstname.lastname@example.org or by calling 1-781-631-7214. Get a copy of the booklet for your lawn service, too.
A yearly schedule
Here are the steps to organic lawn care recommended by the folks at the Living Lawn project in Marblehead.
Early March 'til the end of April
• Assess your lawn: what does it need?
• Test the soil.
• Sharpen mower blades.
• Power rake or aerate to clean up.
• Amend the soil with what your soil test suggests.
• Put down organic fertilizer.
• Put down corn gluten to keep weed seed from germinating, unless you're reseeding.
• Top-dress with compost.
• Mow the first time with the blades at two inches; dispose of clippings.
April to June
• Raise mower blades to three to three and a half inches; leave the clippings on the lawn for all mowings from now until fall.
• Make sure blades are sharp.
• Scout for weeds; pull as needed (mowing weakens them).
• Reseed bare spots.
• Monitor for insect problems.
June to August
• Understand summer stresses; some grasses go dormant.
• Apply beneficial nematodes. Living Lawn recommends these instead of milky spore; they affect more beetle species, including Japanese. Nematodes must be alive, so it's best to mail-order or ask your nursery to order fresh ones for you. Don't buy them off the shelf.
• Look for disease problems.
• Top-dress with rock minerals if your soil test recommends.
• Continue to mow high; leave clippings.
• Water, if necessary, to equal about two inches per week.
Mid-August to Mid-September
• Test soil if you didn't in spring.
• Aerate if you didn't in spring.
• Lime if necessary.
• Fertilize if necessary.
• Reseed as needed.
• Top-dress with compost.
October and November
•Mow while the grass still grows.
• Final mowingreduce blades to two inches.
• Apply organic fertilizer at half usual rate for newly started lawns or patches.
• Remove leaves as they accumulate, or use mulching mower and leave pieces on lawn.
© 2004 The Carlisle Mosquito