These articles are written to apply to the northeastern corner of Illinois. Problems and timing may not apply outside of this area.
Weed Management Options for Gardens
May 22, 1997
With the Memorial Day weekend nearly here, gardeners will be completing plantings, in particular vegetables and annual flowers, soon. As the season advances, hopeful plans for abundant crops and colorful beds often are spoiled by weeds. Consider options now, before weeds ruin your 1997 gardens!
Certainly hand-pulling and cultivation are options for weed control. Cultivate as shallow as possible to avoid bringing up more weeds and to prevent damaging root systems of plants. These methods can be very effective, but only if the gardener is persistent and stays ahead of the weeds. However, vacations, rains, mosquitos, and hundreds of other things to do may allow the weeds to take over if cultivation and hand removal is the only control plan.
Mulching is an excellent weed control option. Mulching provides many benefits to the garden in addition to weed control, including conserving soil moisture, preventing soil crusting, erosion control, more uniform soil temperatures, and a more attractive garden.
Many organic mulch materials are available for use, including straw, hay, crushed corncobs, grass clippings, compost, and leafmold. Shredded bark works well in flower beds. Most organic mulches add organic matter to the soil as they decompose.
Synthetic or inorganic mulches are also used on many vegetable crops. Black plastic (polyethylene film) works well on warm loving crops such as tomatoes, eggplant, and melons. Wait until the soil warms up before putting synthetic mulches down.
Don't use black plastic on perennials, shrubs, or trees, however. Commercially available fabric mulches are a better option for ornamental plants, as they allow air and water to pass through them. These are usually covered with bark or other more decorative mulch material.
Finally, herbicides (weed killers) can be used in vegetable and flower gardens. Preemergence herbicides are put down on the soil at the start of the season to kill weed seeds as they germinate. Two herbicides labelled for many vegetables and flower gardens are DCPA (Dacthal) and trifluralin (Preen, Treflan).
Make certain that all crops or plants you are planning to grow are on the label of the herbicide you plan to use. Often there are crops in the planting that are not on the label, so the herbicide cannot be used. Read, understand, and follow all label directions.