Weed control is part of every successful lawn maintenance plan. Here are some steps you can take to ensure that your grass stays as weed-free as possible.
Also called ground ivy, creeping Charlie thrives in poorly drained shady sites with fertile soil. Rounded leaves with toothed margins form along square stems that weave across the lawn. Blue funnel-shaped flowers appear from April to June. Controlling Creeping Charlie is difficult, especially in shady sites where there’s little competition from grass. Increase sunlight to these areas by pruning trees and shrubs. To control the spread by hand, dig out all the stems and roots or the plant will grow back. For large areas, apply a post-emergent broadleaf herbicide containing dicamba from mid-spring to early summer and in middle to late fall.
• Pull weeds when soil is damp. Hard soil is reluctant to release weeds. Wait a day or two after rainfall to do some hand-pulling or digging.
This perennial groundcover produces three leaflets atop a long stem and small rounded white or pink flowers. If clover has “invaded” your perfect suburban lawn, consider its attributes before removing it. It’s an excellent pollinator plant and a favorite of honeybees. Clover doesn’t require fertilizer or water to remain green during drought conditions and it has no serious pests. In fact, many lawn seed companies include clover in seed mixes because of its low maintenance and environmentally friendly attributes. To prevent a total clover takeover of the lawn, remove small clumps by hand or mow larger areas high—at three inches or more.
• Water infrequently, but deeply. Lawns require about an inch of water per week. Any more than that and you’re inviting disease. Water deeply to promote a stronger root system and only when there’s been insufficient rainfall. A rain gauge positioned in the landscape can help you determine weekly precipitation.
• Dig only when necessary. Thousands of weed seeds sit just below the surface of the soil, waiting to be kissed by the sun. The more you disrupt soil in your beds and lawn, the more you increase the likelihood that seeds will germinate.
Just when you thought that your carpet of green grass couldn’t look any better, a weed pops through to remind you that you are not in control. Unfortunately, weed control is part of any lawn maintenance routine. Whether the seeds blow in on the wind, drop from a passing bird, or lie dormant in the soil waiting for the right time to emerge, it’s inevitable that they will find your grass. A quick response is key to preventing a few weeds from swallowing your entire lawn. Here are nine common lawn weeds and the best (and safest) ways to stop their spread.
Atrazine is effective for preemergence control of chamberbitter in centipedegrass and in St. Augustinegrass lawns. Be careful not to apply on turf during the transition period from dormancy to active growth (spring green-up). Because chamberbitter tends to germinate in late spring and early summer (once the soil temperature reaches 70 °F), applications after grasses fully green up are effective. Target areas where chamberbitter was observed the previous season and be careful to not apply near the roots of desirable landscape plants. See Table 1 for examples of products.
Preemergence Herbicides: Isoxaben can be applied as a preemergence herbicide in landscape beds around certain well-established ornamental shrubs and trees to prevent chamberbitter from growing from seed. Products are best put below the mulch layer. Do not apply preemergence herbicides in beds where new plants will be installed, as plant root development may be inhibited. See Table 1 for examples of products.
Mechanical weed control involves the physical removal of the weed from the soil. This is best accomplished by hand when weeds are young and small or in the seedling stage and easier if the soil is moist. Preventing the weed from reaching maturity and setting seeds also reduces future weed populations.
Chamberbitter grows upright and has a well-developed taproot. The leaves are arranged in two rows on the branchlets and are thin and oblong, with smooth margins, resembling a mimosa seedling.
Within landscape beds, apply two to three inches of mulch in the spring to cover seeds from the previous season. Because chamberbitter seeds require light to germinate, this is especially effective.