Don't leave cold weather weeds unchecked
Is there such a thing as a weed that grows during the winter?
Something creepy may be lurking in your lawn and garden, ready to take over as the temperatures rise - they are the dreaded cool season annual weeds.
These pesky plants take hold in the late summer and autumn, possibly escaping your notice as the growing season comes to a close. Early in the spring as soil begins to thaw, they grow rapidly, striving to flower and seed prior to being yanked from the fertile ground.
If left unchecked, these weeds draw resources and develop hundreds of seeds that lay in wait until next autumn when they begin the growth cycle, and multiply once again. Both warm and cool season annual weeds complete their entire growth cycle within a year.
Winter annual weeds common to Illinois include two pictured here, common chickweed and henbit, in addition to purple dead nettle, lambsquarters and giant foxtail, among others. Summer annual weeds include crab grass and purslane.
The key to controlling all annual weeds is to pull them before they flower and seed. It's relatively easy to spot the cool season annuals as they typically are green very early in the growing season. Be on the lookout for annual and perennial weeds that take hold and grow over multiple years, like dandelion and quack grass. Left unchecked, perennial weeds seed and form root systems that grow aggressively, making removal difficult. Identifying and removing weeds while they are just getting established can save hours of work later on.
Keep weeds to a minimum using the following strategies:
In the garden, use a 2- to 3-inch layer of mulch between plants and avoid watering uncultivated areas. Rather than cultivating the entire garden, turn over soil only where seeds or plants will reside. Each time soil is turned, it exposes latent seeds to air and sun, sparking germination. If broad cultivation is required, let soil rest a few weeks and remove unwanted sprouts as they emerge.
In the lawn, strive to keep turf thick and healthy. Reseed bare spots and don't allow weeds to flower and seed. Water deeply once per week to promote turf with a deep root system vs. frequently sprinkling the lawn lightly. Mowing annual weeds before they flower will help keep them from spreading.
- Olga DeSio
• Provided by Master Gardeners through the Master Gardener Answer Desk, Friendship Park Conservatory, Des Plaines. Call (847) 298-3502 or email northcookmg@gmail.com.