Who is answering my gardening questions on Ask Garden Guy?

Todd Farber — a Texas A&M horticulture graduate and Houston native with 33 years of landscaping experience. He’s the trusted voice behind Ask Garden Guy, helping Houston and Sugar Land homeowners with real, local answers.

Is Ask Garden Guy related to GardenLine on KTRH?

We’re not affiliated with KTRH or GardenLine, but we’re proud to continue the spirit of helpful garden talk! Many former GardenLine listeners now use Ask Garden Guy to get timely advice without calling in or waiting on hold.

How does Ask Garden Guy work?

Just submit your question online—photos welcome—and you'll receive a real response from Garden Guy or our small Houston-based team. No bots, no scripts, just time-tested advice tailored to your yard.

Is there a fee to ask a question?

Nope. Ask Garden Guy is free. For personalized in-person consultations, our paid landscaping design team at Garden Guy is also available at gardenguy.com.

Are bugs in compost normal?

Yes! Bugs like wood roaches (palmetto bugs) and ants are common in compost piles. They help break down materials. To reduce them, keep your pile moist and add more greens.

What’s the best compost ratio for Houston yards?

Aim for 2 parts browns (dry leaves, pine needles) to 1 part greens (grass clippings, kitchen scraps, coffee grounds). This balance helps compost break down quickly.

Can I compost Bermuda grass?

Only if your compost pile reaches 140°F+. Otherwise, Bermuda runners can survive and regrow when you spread compost later.

What perennials grow best in Houston?

Texas sage, lantana, salvias, Gulf Coast muhly grass, drift roses, loropetalum, and Esperanza are consistently reliable performers in Houston's heat, humidity, and soil conditions.

When is the best time to plant perennials in Houston?

Fall and early spring are the best times to plant perennials in Houston because those seasons allow strong root development before summer heat arrives.

Do perennials survive Houston freezes?

Most Houston-friendly perennials survive freezes, but some go dormant. Avoid cutting back freeze-damaged plants until spring when new growth appears.

When should I apply pre-emergent in Houston?

Apply pre-emergent by February 1st, before soil temperatures consistently reach 55°F. That's the threshold at which warm-season weed seeds like crabgrass begin to germinate. Use a soil thermometer to confirm — once the soil hits 55°F, the window has closed.

When should I fertilize my St. Augustine lawn in Houston?

When the lawn tells you it's ready — not when the calendar does. Watch for nighttime temperatures above 55°F for at least 5 consecutive days and your grass actively greening with new growth. In Houston this typically happens between late March and early May, but it varies year to year.

When should I fertilize Bermuda grass in Houston?

When it's fully green and you've mowed it at least twice. Bermuda wakes up later than St. Augustine — usually late April or May in Houston, but a cold spring can push it later.

Do I need to add a surfactant to my weed killer?

Yes — always. A non-ionic surfactant helps herbicide spray stick to the waxy surface of weed leaves and penetrate the plant. Without it, much of your spray runs off and loses effectiveness.

Should I get a soil test for my Houston lawn?

Yes — especially if you've been fertilizing and still not seeing results. Houston clay varies yard to yard. A Texas A&M soil test tells you exactly what's missing before you spend more money on product.

What is nutsedge and how do I identify it in my Houston lawn?

Nutsedge (also called nutgrass) is a sedge — not a grass or broadleaf weed — that is extremely common in Houston and Gulf Coast lawns. To identify it, pull a stem and roll it between your fingers. If it has three distinct sides like a triangle, it is nutsedge. It is also a lighter yellow-green color than surrounding turf, grows noticeably faster, and sends up three leaves from a single shoot at the base. Regular grass sends up two.

Why does nutsedge keep coming back no matter what I spray?

Nutsedge keeps coming back because it spreads through underground tubers called nutlets that regular weed killers cannot reach. A single nutsedge tuber can produce up to 7,000 new tubers in one growing season. Regular broadleaf weed killers and weed-and-feed products have no effect on nutsedge because it is a sedge, not a broadleaf. You need a selective sedge herbicide like Sedgehammer (halosulfuron) or Dismiss (sulfentrazone).

Why does pulling nutsedge by hand make it worse?

Pulling nutsedge by hand snaps the plant from its underground nutlet chain but leaves those nutlets in the soil. Each nutlet then sprouts into multiple new plants. Hand-pulling does not remove nutsedge — it multiplies it. The same problem occurs with rototilling without a follow-up herbicide program.

What is the best herbicide for nutsedge in St. Augustine or Bermuda grass in Houston?

Sedgehammer (halosulfuron-methyl) is the top recommendation for Houston homeowners with St. Augustine or Bermuda lawns. It is safe for both grass types, can be used throughout the growing season, and works systemically to attack the root system and tubers. Dismiss (sulfentrazone) is a good alternative when faster visual results are needed. Always add a non-ionic surfactant to either product — nutsedge has a waxy leaf surface that causes sprays to bead up and roll off without it.

How do I kill nutsedge near vegetables, flowers, or garden beds without harming other plants?

Use the Q-tip method. Mix Sedgehammer at the standard label rate with surfactant in a small cup. Put on gloves, dip a cotton swab or small foam brush into the solution, and carefully wipe it directly onto the nutsedge leaves. Avoid contact with surrounding desirable plants. The product absorbs through the leaf surface and moves down to the roots and tubers. This is the safest approach for vegetable gardens, raised beds, mixed flower beds, and containers where spraying would risk damaging other plants.

What is Kyllinga and how is it different from nutsedge?

Kyllinga (pronounced kuh-LING-uh) is a closely related sedge that is frequently mistaken for nutsedge in Houston lawns. The key difference is the seed head — Kyllinga has a small round ball-shaped seed head, while nutsedge has an open branched umbrella shape. Kyllinga also has glossier leaves, a distinctive minty-sweet scent when crushed, and spreads by forming dense low mats. The same selective sedge herbicides that control nutsedge — Sedgehammer and Dismiss — also work on Kyllinga.

How many treatments does nutsedge take to control?

Nutsedge typically requires 2 to 3 treatments spaced 6 to 10 weeks apart in the first season, with follow-up the next season as dormant nutlets continue to germinate. This is normal and expected. The goal of each application is to prevent new plants from maturing and producing more tubers. Most Houston homeowners see meaningful improvement by the second season of a consistent program using Sedgehammer or Dismiss with a non-ionic surfactant.

Does overwatering cause nutsedge in Houston lawns?

Yes. Nutsedge thrives in consistently moist soil, making overwatered lawns, low spots, and areas with irrigation heads that run too frequently prime targets. Even after a correct herbicide treatment program, nutsedge will keep returning if the underlying moisture issue is not addressed. Check your irrigation schedule and look for drainage problems in areas where nutsedge pressure is heaviest.

Why is my St. Augustine turning yellow even though I fertilized?

Almost always Houston's alkaline clay blocking iron uptake. A liquid iron application usually fixes it within days — adding more nitrogen won't.

What's eating my lawn overnight?

In late summer and fall, armyworms are the most common culprit — they can strip a lawn to bare soil within 48 hours. Heavy bird activity on the lawn is often the first warning sign.

My grass has circular brown patches — is that a fungus?

Likely brown patch, and it's almost always tied to overwatering rather than a product problem. Fixing your watering schedule solves it more often than fungicide does.

Is it too late to put down pre-emergent?

Once your soil is consistently above 55°F, pre-emergent won't stop that season's weeds — they've already germinated. A soil thermometer takes the guesswork out.

Sod Webworms in Houston St. Augustine Lawns | Garden Guy

Houston Lawn Update — June 20, 2026

Sod webworms are starting to show up again in Houston St. Augustine lawns, and Garden Guy is already getting questions about them.

This matters because sod webworms can move fast.

One Houston-area homeowner recently told Ask Garden Guy that sod webworms had “about eaten” her yard and the neighbor’s yard several years ago. After the grass was damaged, weeds moved into the bare spots.

That is the part most lawn advice skips.

Sod webworms are not just a “spray and forget” problem.

First, you have to confirm what is actually happening.

Then you treat correctly.

Then you repair the damaged lawn so bare spots do not become a weed hotel.

Let’s walk through it.

What Are Sod Webworms?

Sod webworms are lawn-damaging caterpillars.

Sod webworm caterpillar in St. Augustine grass

The little moths you may see flying low over your lawn are the adult stage. The moths are a warning sign, but they are not what actually chew up the grass.

The damage comes from the larvae.

Garden Guy rule:

The moths are the warning light.
The worms are the engine problem.

If you see tiny moths fluttering over the lawn, especially near areas of thinning or damaged St. Augustine, do not panic. But do inspect.

Why Houston St. Augustine Lawns Can Get Sod Webworms

Houston gives sod webworms plenty to enjoy:

Hot weather.

Humidity.

Thick St. Augustine.

Thatch.

Stressed lawns.

Rain followed by heat.

Overwatered areas.

Overfertilized areas.

Lawns that are already struggling.

Sod webworm damage can appear quickly and may look like the grass was clipped too short, chewed down, scalped, or browned in patches.

Signs of Sod Webworm Damage in St. Augustine

Look for these symptoms:

✓ Ragged grass blades
✓ Chewed or notched leaf tips
✓ Grass that looks unevenly clipped
✓ Brown or scalped-looking patches
✓ Tiny caterpillars in the thatch
✓ Small green or brown pellets, called frass
✓ Fine webbing or silken tunnels near the soil surface
✓ Damage that seems to spread quickly

The best place to inspect is usually not the completely dead center of the damaged area.

Check the edge where healthy grass meets damaged grass. That is often where the active feeding is happening.

Are the Lawn Moths Sod Webworms?

Maybe.

Small moths fluttering low over the lawn can be a clue, but moths alone are not a diagnosis.

You need to look for larvae or fresh chewing damage.

The moths are the adult stage. The caterpillars are the stage that damages your lawn.

So if you see moths, inspect the grass.

If you see chewed blades, inspect harder.

If you find active larvae, then you treat.

How to Check for Sod Webworms

Here is a simple homeowner inspection process.

1. Look closely at the grass blades

Part the grass and look down into the thatch layer.

You are looking for:

✓ Chewed blades
✓ Tiny caterpillars
✓ Small pellets/frass
✓ Webbing
✓ Active feeding at the edge of the damaged patch

2. Check at the edge of the damage

The edge between good grass and bad grass is usually more helpful than the dead center of a brown patch.

The dead center may already be abandoned.

3. Try a soap flush test

A soap flush can help bring sod webworm larvae to the surface.

Mix a small amount of liquid dish soap into water and pour it over a small test area near the edge of the damage. Watch for several minutes. If caterpillars are present, they may come up to the surface.

This is not glamorous.

This is lawn detective work.

Welcome to Houston.

Sod Webworms vs. Brown Patch in St. Augustine

Sod webworm vs. brown patch comparison chart for St. Augustine grass lawns in Houston, showing chewed blades and a caterpillar versus circular brown patch fungus with rotted blade bases. Sod webworms chew St. Augustine grass blades. Brown patch is fungal and often causes blades to pull loose from rotted leaf sheaths. Diagnosis matters before treatment.

Free Field Guide

This is where homeowners get confused.

Both sod webworms and brown patch can make St. Augustine look brown, patchy, and terrible.

But they are not the same problem.

Sod webworms are chewing insects.

Brown patch, also called large patch, is a fungal disease.

Garden Guy distinction:

If the grass blades are chewed, think caterpillar.
If the blades pull loose from a rotted sheath, think fungus.

With sod webworms, you are looking for chewing damage.

With brown patch, the lower part of the grass blade may rot where it attaches to the runner. Yellowing blades may pull loose easily.

That is a fungus clue, not a caterpillar clue.

And because Houston lawns enjoy being dramatic, yes, a lawn can have more than one problem at the same time.

A stressed St. Augustine lawn can be dealing with insects, fungus, poor drainage, bad watering, mowing stress, and weak soil all at once.

That is why diagnosis matters.

Should You Treat Sod Webworms Every Year?

Not automatically.

If you have had sod webworms before, you should absolutely watch for them during the hot Houston lawn season, especially summer into early fall.

But Garden Guy does not recommend panic-spraying every year just because you are scared.

That is not lawn care.

That is emotional support spraying.

Inspect first.

Confirm the issue.

Then treat.

Best Sod Webworm Treatment Options for Homeowners

Always read the current product label before buying or applying anything.

The label is the law.

Here are three Amazon-available homeowner lawn insecticide options to consider when sod webworms or lawn caterpillars are confirmed.

1. BioAdvanced Complete Brand Insect Killer for Soil & Turf

Amazon link:
https://amzn.to/3QqCQ9n

This is a lawn insecticide option for listed turf insects.

Use this type of product when you have confirmed or strongly suspect active lawn insects such as sod webworms, armyworms, cutworms, chinch bugs, or other listed turf pests.

Do not use it just because the lawn looks brown.

Brown can mean many different things in a Houston St. Augustine lawn.

2. Ortho BugClear Insect Killer for Lawns & Landscapes

Amazon link:
https://amzn.to/3QtXvtc

This is another common homeowner lawn and landscape insecticide option.

It is an insect-control product, so it fits the conversation when you are seeing chewing damage, moth activity plus larvae, or other signs of listed lawn insects.

Again, read the product label.

Do not guess.

Do not overapply.

Do not spray before rain.

3. Spectracide Triazicide Insect Killer for Lawns & Landscapes

Amazon link:
https://amzn.to/3QBscg3

This is another lawn insecticide option for listed outdoor insects, including many common turf pests.

Use it only according to the label and only when the problem fits.

This is not a brown patch treatment.

This is not a “my lawn looks sad” treatment.

This is an insect-control option.

Important Sod Webworm Treatment Notes

Before applying any lawn insecticide:

✓ Read the label before you buy
✓ Read the label again before you spray
✓ Apply only at the labeled rate
✓ Keep children and pets off the lawn until the label says it is safe
✓ Do not apply before heavy rain
✓ Do not apply when product may run off
✓ Do not let it wash into streets, storm drains, ditches, creeks, ponds, pools, or bayous
✓ Avoid spraying blooming weeds or plants where pollinators are active
✓ Do not mix products unless the label allows it
✓ Do not treat a stressed lawn like it owes you money

Evening application is often a better fit for sod webworm activity because they feed at night.

What About Organic Sod Webworm Treatment?

If you are trying to stay organic and you confirm small, actively feeding caterpillars, BT products may help.

BT stands for Bacillus thuringiensis.

BT works best when caterpillars are small and actively eating treated foliage. It is not the same as a fast knockdown broad-spectrum insecticide.

For a heavy infestation where the lawn is actively being eaten, many homeowners choose a labeled turf insecticide.

After the Sod Webworms Are Gone

This is the part almost nobody talks about.

The treatment may stop the chewing, but it does not magically rebuild the lawn.

After treatment, you still have to evaluate the grass.

Step 1: Recheck the Lawn

Inspect the damaged area again several days after treatment.

Look along the edges.

Check for fresh chewing.

Use a soap flush again if needed.

You want to make sure the larvae are gone before you start deciding what the lawn needs next.

Step 2: Rake Out Dead Material

Remove matted, dead, chewed grass.

Do not leave a wet thatch blanket sitting over the soil.

That only makes recovery harder.

Step 3: Check the St. Augustine Runners

St. Augustine spreads by runners, also called stolons.

If the runners are still alive, firm, and green at the nodes, the lawn may recover with correct watering, mowing, and time.

If the runners are dead, crispy, loose, and detached, that area may not come back.

Step 4: Do Not Panic-Fertilize

A chewed-up, stressed lawn does not need someone dumping high-nitrogen fertilizer on it in the heat.

That can make other problems worse.

The lawn needs correct watering, oxygen, sunlight, healthy runners, and time.

Not a fertilizer tantrum.

Step 5: Deal With Weeds in Bare Spots

Bare spots invite weeds.

That is exactly what happened in the Ask Garden Guy question that prompted this article.

The sod webworms damaged the lawn, the grass thinned out, and weeds moved into the open space.

If weeds have taken over the dead areas, the long-term fix may not be “spray more stuff.”

Sometimes the correct answer is to clean out the damaged area and re-sod correctly.

How to Re-Sod After Sod Webworm Damage

Garden Guy is very firm on this:

We do not lay sod on hard, bare, compacted dirt and call that a lawn installation.

That is green carpet with commitment issues.

If sod webworms destroyed sections of the lawn and the area is truly dead, the correct repair process is:

✓ Scrape out dead grass
✓ Remove weeds and debris
✓ Loosen compacted soil
✓ Lay down enriched topsoil
✓ Grade and level properly
✓ Lay fresh St. Augustine sod tightly
✓ Lay seams tight
✓ Press sod for good soil contact
✓ Water correctly while it roots
✓ Taper watering as the sod establishes

Sod needs soil contact.

It needs oxygen.

It needs water.

It needs preparation.

It does not need to be thrown on top of concrete-hard Houston clay and abandoned in July.

Free Houston Garden Tips Each Week

Frequently Asked Questions About Sod Webworms in Houston

What do sod webworms look like?

Sod webworms are small caterpillars. They may be light brown, grayish, or greenish depending on age and species. The moths are small and often fly low over the lawn.

Do sod webworm moths damage the lawn?

No. The moths do not chew the lawn. The larvae/caterpillars do the damage.

What does sod webworm damage look like?

It can look like ragged, chewed, clipped, scalped, thinning, or brown St. Augustine grass.

Can sod webworms kill St. Augustine?

They can severely damage it. If the runners remain alive, St. Augustine may recover. If the runners die or weeds take over the bare areas, re-sodding may be needed.

Is brown patch the same as sod webworms?

No. Brown patch is fungal. Sod webworms are insects. Chewed grass points toward caterpillars. Grass blades pulling loose from rotted sheaths points toward fungus.

Should I treat sod webworms every year?

Not automatically. Watch for them if you have a history, but treat only when you confirm active larvae or fresh damage.

What is the best time to treat sod webworms?

Evening is often a better fit because sod webworms feed at night. Always follow the product label.

What should I do after treating sod webworms?

Recheck the lawn, rake out dead material, inspect the runners, avoid panic-fertilizing, manage weeds, and re-sod correctly if the grass is truly dead.

Garden Guy Bottom Line

Sod webworms are not mysterious once you know what to look for.

Remember:

✓ Moths are a clue, not the diagnosis.
✓ Larvae are what damage the lawn.
✓ Chewed blades point toward caterpillars.
✓ Rotted leaf sheaths point toward fungus.
✓ Treat only when needed.
✓ Use a labeled product.
✓ Read and follow the label.
✓ Recheck after treatment.
✓ Repair the lawn correctly afterward.

Diagnosis first.

Treatment second.

Recovery plan third.

That is how you keep one Houston lawn problem from turning into five.

Need help with a Houston St. Augustine lawn problem? I’m Todd Farber, Aggie Horticulturist and expert Houston landscaper. I am happy to help you with my link below.

Ask Garden Guy here:
https://www.askgardenguy.com

Sod Webworms in Houston St. Augustine Lawns: How to Find, Treat, and Repair the Damage