A photo of a weed named Hairy Bittercress. It is leggy with white blooms.

Hairy bittercress

The warm-season grasses are starting to spout, so now’s the time to give your yard a close inspection. For Bermuda, zoysia and centipede lawns, the brown dormancy of winter has broken, and with it comes the onslaught of summer weeds.

If you act in early April, you may be able to prevent some of these weeds with a late – very late – application of preemergent. Use a dedicated pre-emergent, not a combo fertilizer/weed killer. And read package instructions to learn the rate of application. Pre-emergents will need to be watered in.

With only about 25 percent green, go ahead and use the preemergent. Weed seeds germinate at varying soil temperatures, so a late application of preemergent this month is a step in the right direction and could curtail weeds that emerge in the early to mid-summer.

Bermuda will be the first to green up, but zoysia and then centipede will fill in by mid-May to create a lush green lawn. It’s easier to identify darker green spring and summer weeds when you are looking at a brownish lawn.

Weeds like henbit, chickweed, dandelions, dallisgrass, poa annua, hairy bittercrest and bluegrass – if they’re not too widespread – can easily be hand-pulled. Remove them as soon as they appear and before the seedheads ripen; the seeds can survive in the soil for several years.

Tougher weeds are better dug out with a hand-spade. Loosen the soil around clover and wild onion, then remove the plants.

Nutsedge with its dark green narrow blades that grow in clumps, require a liquid weed killer. Garden experts recommend a product called “Image,” formulated for stubborn nutsedge. Read the package label and apply according to the instructions. Several applications will be needed every 10 days or so to eliminate nutsedge. It will not harm your Bermuda or zoysia.

Other lawn chores

April and May are the best time to aerate your warm-season lawn. Aeration helps break up hard soil and allows both air and water to get to the roots. It encourages root growth, which will help ensure a healthier lawn. And when you fertilize afterward, the nutrients can also penetrate more deeply.

Check your lawn mower

When did you sharpen your mower blades? These should be cleaned, sharpened and cleared of rust regularly. Between mowings remove any grass clippings that have clumped underneath.

Check the oil and other fluids at the beginning of the season to ensure a longer life for the mower.

Pay attention to mowing heights, which vary depending on the type of grass you have. Most warm-season grasses thrive at between 2 and 2.5 inches, and a bit longer when it’s hot to protect the roots by keeping them a little cooler.

A word about watering

Healthy lawns thrive on deep watering, which encourages deep root growth. Once-a-week watering is ideal, applying between 1 and 1.5 inches each time. Place several tuna cans or cat-food cans around your lawn to accurately measure the amount of water you’re using. Adjust your irrigation system accordingly to apply one to 1.5 inches a week all in one watering session.

Water in the early morning to allow the grass to dry thoroughly; this will reduce the chance of lawn diseases.

If we get a soaking rain, you can cut back on supplemental watering.

To learn more about lawns, grasses and lawn care, visit extension.uga.edu and click on publications. They’re free and downloadable, with information about everything from plant-specific pruning, to proper lawn irrigation.

Photo: courtesy Pixabay, Cardamine Hirsuta