Environmentally Friendly Control of Weeds in the Lawn
My bluegrass lawn is overrun with weeds. I want to get rid of the weeds this fall while being kind to the environment.
Start with a healthy lawn. This is your best defense against weeds. Mow high, 2 1/2 to 4 inches and often enough to remove no more than an inch at a time. Leave your grass clippings on the lawn. They add water, nutrients and organic matter to the soil.
Fertilize to keep your lawn healthy and reduce weed problems. Research has found that one fertilization a year can greatly reduce the weed population in a lawn. Fertilize at Halloween if you chose to make just one application. Otherwise, increase the health and vigor of your lawn by following the holiday fertilization schedule and make applications on Memorial Day, Labor Day and Halloween).
You can allow your lawn to go dormant during drought. It will survive but the weed population will increase. If you do water, water thoroughly whenever your footprints remain in the grass.
Dig weeds, roots and all, this fall. This is time consuming but the most environmentally friendly method. Use a corn gluten pre-emergent in fall and spring to reduce the number of weed seeds sprouting in the grass. You should be able to reduce your weeds by about 50% over a three year period.
Some of the newer herbicides use vinegars, plant acids and soaps to burn off the tops of plants. Repeated applications are needed for perennials and they can damage the surrounding grass as well. Be sure to read and follow all label directions if you try these products. Minimize the negative impact of traditional weed killers by spot treating problem areas instead of treating the whole lawn.