April 22, 2009

Breaking your lawn's addiction to pesticides

As published in The Erin Advocate

Every year, I look forward to the burst of colour on my lawn that confirms the arrival of warm, spring weather. Living out in the country, I have made a virtue of necessity, learning to love the dandelion and its many cousins. There are too many to pluck and I have no desire to attack them with chemicals.

For those who maintain formal distinctions between the "good" and "bad" plants, things have just become more complicated. To celebrate Earth Day today (April 22), the Ontario government has put into effect its Cosmetic Pesticide Ban Act. More than 250 products are now banned from sale, including many popular insecticides, herbicides and weed-and-feed mixtures.

Golf courses are exempt, along with specialty turf users such as lawn bowling clubs, but even these must make public their plans to minimize pesticide use. Farming and forestry are exempt, and you can still use chemicals to control poison ivy, giant hogweed, stinging insects and various indoor pests.

Ontario Environment Minister John Gerretsen says the new rules eliminate an "unnecessary risk to our environment, our families, and especially our children". According to the David Suzuki Foundation, "Researchers have found that pesticides can be associated with serious illnesses, including cancer, damage to the immune system and neurological problems."

Although there is the possibility of lower-risk biopesticides, many people may revert to old-fashioned methods of developing a healthy lawn. Naturally, there are businesses ready to help.

Dave Dittmar of Backyard Organics in Guelph was the guest speaker at the first of three events sponsored by the Climate Change Action Group of Erin (CCAGE), held recently at Centre 2000. His firm helps clients "grow healthy food and landscapes using ecologically sound methods".

Many lawns have become dependent on pesticides, requiring high levels of watering and maintenance to appear healthy, he said. Fertilizers that are not well-absorbed by your lawn are likely to be washed away by the rain, adding to pollution in our waterways. Some people have replaced their lawns with attractive alternatives, but the idea of a green open space is still very appealing.

"Lawns should not be toxic zones or water hogs," said Dittmar. "These are not intrinsic qualities of a lawn, but the result of chemical lawn maintenance. It requires a shift in the way you think about a lawn, look at a lawn and feed your lawn."

A truly healthy lawn requires lots of microbes in the soil to enable plants to absorb nutrients, but pesticides kill off many microbes. Dittmarr advocates a boost in microbes and slow-release nutrients by coating the lawn with lots of high-quality compost in the spring and fall, especially if you are trying to make the transition away from chemicals.

"If there only one thing you're going to do, top-dress with compost as thick as possible, even two to three inches. Hammer it on there, and your lawn will thank you for it," he said.

Follow up with over-seeding, using a mixture of different seeds that will be more hardy than a single species. The initial cost of this process will pay off with reduced maintenance costs in the long term, he said.

When you cut your lawn, set your mower to its highest possible level, and leave the clippings as free fertilizer. Thicker, longer grass, with strong, deep roots will crowd out many weeds and make your lawn less vulnerable to insect damage. Longer grass also shades the soil, allowing it to retain more moisture and still look good during dry spells. You can also aerate, with a machine that removes plugs of soil from a lawn to help water and nutrients reach the roots.

For those not ready to go for the full compost treatment, Dittmar suggests Compost Tea. You will need a special machine to brew it ($140 US at www.simplici-tea.com). Essentially, a pump bubbles air through a container with water and a small amount of compost, producing a supply of microbe-rich liquid that you can spray on your lawn.

Find out more about healthy lawns at www.backyardorganics.ca, www.organiclandscape.org, or search out lawns on the Health Canada website, www.hc-sc.gc.ca.

Lorraine Johnson, author of "100 Easy-To-Grow Native Plants for Canadian Gardens", is the next speaker in the CCAGE Environmentally Sustainable Gardening Series. It is on Wednesday, May 13, 7-9 p.m., in the Shamrock Room at Centre 2000. Admission is $5.00. She will show how it is possible to achieve beautiful, low-maintenance gardens – naturally resistant to pests and requiring little or no watering. CCAGE is also planning a self-guided Organic Gardening Tour in June.