Can you identify the weed in my yard?

Yes. Send us a photo at askgardenguy.com/advice and Todd Farber, our Aggie horticulturist, will tell you what it is and how to get rid of it. That's the difference with this guide: there's a real expert on the other end.

How do I identify a weed in my Texas lawn?

Start with the stem and leaf. A triangular stem means a sedge, like nutsedge. Round or flat hollow stems mean a grassy weed. Wide leaves with veins mean a broadleaf weed. Then match it to the photos above and check its giveaway. Still not sure? Send us a photo through askgardenguy.com/advice.

What kills weeds without killing St. Augustine grass?

For most broadleaf weeds and kyllinga, Celsius WG is safe on St. Augustine. For nutsedge, use Sedgehammer. Grassy weeds are the hard part: nothing selectively removes Bermuda, dallisgrass or torpedograss from St. Augustine. Dig or spot-kill those, then patch with sod. Each weed above shows whether its fix is safe on St. Augustine, Bermuda and Zoysia.

Does Celsius kill every lawn weed?

No. Celsius WG is labeled for 22 of the 33 weeds in this guide, including doveweed, Virginia buttonweed, dollarweed, chamberbitter, clover, henbit and lawn burweed. It does not control nutsedge, Poa annua, Bermuda or torpedograss, and it only suppresses dallisgrass. Don't use it on a Bahia lawn.

Should I add surfactant to my weed killer?

It depends on your grass and your product. Add non-ionic surfactant to the Sedgehammer bottle and to Celsius on Bermuda or Zoysia. Do not add it to a Celsius spot spray on St. Augustine, to ready-to-use bottles, or when it's 90°F or hotter. For everything else, follow the label.

When is the best time to spray weeds in Texas?

Spray winter weeds like henbit, burweed and chickweed from November to February while they're small, before they flower or form burrs. Hit summer weeds like doveweed and buttonweed early in the season while they're young. Spray in the cool of the morning with no rain coming. Pre-emergents go down in late January to February for summer weeds and September to October for winter weeds. North Texas runs a few weeks later in spring.

Can I get Bermuda grass or dallisgrass out of St. Augustine?

Not with a spray that leaves the St. Augustine unharmed. For patches, dig them out with every runner and root, or spot-kill them with glyphosate, then re-sod the spot. Keep the St. Augustine thick, watered right and fed so it doesn't leave room for them.

Is weed-and-feed a good idea?

We don't recommend it. Weed-and-feed spreads herbicide over the whole lawn to reach a few weeds, and the right time to feed rarely matches the right time to treat weeds. Spot-spray the weeds you have, and feed the lawn on its own schedule.

Why do the weeds keep coming back?

Usually it's the conditions, not the spray. Dollarweed, nutsedge, kyllinga and doveweed mean too much water. Clover and lespedeza mean a hungry lawn. Crabgrass and spurge mean thin, bare spots. Fix the cause, and remember that weeds that come back every year need 2–3 treatments over a season or two.

Is this guide just for Houston?

No. It's written for warm-season lawns all over Texas: St. Augustine, Bermuda and Zoysia. The timing is set for the Gulf Coast, and North Texas runs a few weeks later in spring and earlier in fall. Fescue lawns need different products.

Garden Guy · Texas Lawn Weed Guide · Free

The Texas Lawn Weed Guide

33 Texas lawn weeds with photos, and for every one, what kills it without killing your St. Augustine, Bermuda or Zoysia.

Most weed ID pages stop at the name. This one goes all the way to the fix: the giveaway that tells you which weed it is, whether the treatment is safe on your grass, when to spray, and the exact product to buy. Still not sure? Send Todd a photo and he'll identify it for you, free. No other weed guide has an expert on the other end.

By Todd Farber, Aggie horticulturist · Garden Guy, since 1991