Gardening: To control chickweeds, timing is everything

Right now, chickweed is having a heyday in the garden spreading its mats of bright green leaves over any available piece of bare ground. Where did it come from you say? That’s this week’s adventure in gardening.

There are two types of chickweed here; common chickweed and mouse-eared chickweed.

Common chickweed is an annual that thrives in the cool weather in the fall through into the spring. It forms spreading mats of bright green, small round leaves in fragile stems that get about 2 inches tall but can spread 2 feet or more. It’s tiny, star-shaped, white flowers are blooming right now and will quickly set seed. And therein lies the challenge to controlling it. It’s an annual that is already done for the season and you’ve barely started your spring gardening.

The seeds will lie dormant until the weather cools in the fall and then sprout. The new plants then grow slowly through the coldest part of the winter before exploding through the garden as the weather begins to warm in the spring. This means that to control chickweed you must start early in the fall.

Clean up your beds in the fall and then cover them immediately with 3 to 4 inches of mulch, such as shredded leaves or pine needles, compost or grass clippings. Get creative. I used burlap coffee bean bags from local coffee roasters on my raised beds where I had a problem with chickweed and its gone. Cardboard would also work. The goal is to block the light the plants need to grow.

To deal with it now, dig out the clumps; they are fairly shallow-rooted but dense. Throw them in the trash rather than the compost pile or the green bin because they are loaded with seeds that are hard to kill. Get some mulch on the soil as is noted above.

Mouse-eared chickweed is a perennial and found most often in lawns and bare areas. It is a darker green and has smaller leaves than common chickweed. The name comes from the fact that the leaves are fuzzy like a mouse’s ear. Like common chickweed, mouse-eared chickweed is shallow rooted and can be dug or pulled out. However, it will regenerate from roots left in the ground, so it may be necessary to make sure you get all the root. It also spreads easily as stem grow from the mother plant and set roots.

Because both chickweeds are winter annuals, controlling them with herbicides is difficult.Timing is everything.

The best time to treat them is in the fall when they germinate. However, that means you need to watch for the new plants and get the herbicide (2,4D products) on them when the temperatures are still above 50 degrees. Below 50, most herbicides don’t work well.

You can also apply pre-emergent herbicides in late September that will prevent the seeds from germinating.

Either way, getting rid of chickweed is a challenge and may take more than a single year. Be patient and be persistent.