It’s best to take control early with weeds

Flowers are starting to bloom, seemingly dead plants are coming back to life and allergies continue to go wild. Spring is welcome at my home everything but the drippy nose and the pesky lawn weeds.

Unfortunately, I cannot do much about the allergies; however, I can help with the weeds. If you are already dealing with henbit or chickweed and are awaiting the arrival of crabgrass later this season, here are a few tips to help you get a jump on a lawn weed-control program.

Henbit is a rather showy spring-blooming weed. The violet flowers, born on stems 8 to 12 inches tall, are quite striking on a warm April day. They are commonly found in cultivated areas such as farm fields, flower beds, gardens and lawns.

Chickweed, on the other hand, has a lower growth habit with creamy yellow blooms. Together the two plants can create a beautiful spring display with little effort. But as with most weeds, they can be invasive and easily take over if left unattended.

Controlling both weeds can be simple if you start now. Begin with mechanical controls. Hoe or lightly till weeds growing in the garden and around flowers, trees and shrubs. These weeds only reproduce from seed, so if the flowers are not allowed to mature seed will not be dropped for weeds to grow next year.

In the lawn area, mowing low and catching the clippings will prevent seed dispersal and decrease the amount of future weeds.

For hard-to-reach or noncultivated areas, the broadleaf weed killer Trimec is the best product to use. Spray on a sunny day when temperatures are above 55 degrees. Avoid spraying newly sprouted grass seed, as dieback may occur.

When using Trimec take care to not spray desired plants that are emerging. Trimec contains 2-4D, a broadleaf weed killer that can severely damaged many landscape trees and shrubs.

Crabgrass control is a different story. The best method is prevention. Traditionally, pre-emergent herbicides are used this time of year to prevent growth of this common lawn weed.

Barricade and Dimension are two commonly available crabgrass preventers. Barricade can be applied in the fall for crabgrass control the following season.

Dimension is unique in that it can be applied after the crabgrass has germinated, as long as the plants are still small. And for all you procrastinators, Dimension can be applied through early May with good results.

Both products have longer residual activity than other crabgrass preventers. This means two things: You can apply these herbicides early in the spring and you will not have to make a second application, as with some other products.

Tupersan is a product that can be used at the time of seeding. It is somewhat less effective than other pre-emergent herbicides but does not harm the newly seeded grass. Tupersan provides short-term control so an additional application will be necessary about six weeks after the first.


Bruce Chladny is horticulture agent at K-State Research and Extension-Douglas County. For more information, call him at 843-7058 from 8 a.m. to 5 p.m. weekdays.