Lambsquarter Control

Lambsquarter weed reproduces only through seeds. Most lambsquarter seeds germinate in late spring or early summer, although they can continue to germinate throughout the growing season. The plants flower in late summer or early fall, and are followed by an abundance of seeds. The average lambsquarter weed plant produces 72,000 seeds that can live in the soil and germinate 20 years or more after they are deposited.

Lambsquarter control in the garden begins with hand pulling and hoeing to remove the weed, and mulching. Lambsquarter has a short taproot, so it pulls up easily. The goal is to remove the weed before it matures enough to produce seeds. The plants die with the first frost, and next year’s plants grow from the seeds they leave behind.

Consistent mowing to keep lawns at the recommended height will cut down lambsquarter weed before it has a chance to produce seeds. Aerate the lawn if the soil is compacted and minimize foot traffic over the grass to give the lawn a competitive edge over lambsquarter. Maintain a healthy lawn by following a regular schedule of watering and fertilization.

Herbicides also help control lambsquarters. Pre-emergent herbicides, such as Preen, prevent the seeds from germinating. Post-emergent herbicides, such as Trimec, kill the weeds after they germinate. Read the label on the herbicide product of your choice and follow the mixing and timing instructions exactly .