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.

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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.

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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.

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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.

Is My Houston Lawn Dead, Dormant, or Just Thatch? A Photo Guide

Houston lawn tipsDiagnose Lawn Problems

Nov 6

Written by Sabrina Farber

Houston Lawn Help · Fall & Winter

Y'all have been sending us a lot of lawn photos now that it's cooling off. Here's the good news: most of those lawns are perfectly healthy.

What most of you are seeing in November isn't dormancy yet. It's thatch: old brown blades and stems at the base of the grass that show up once growth slows down. Here in Houston, St. Augustine usually doesn't go truly dormant until December or January, after our first freeze.

A few real lawn problems show up this time of year too, and they can look similar at first glance. So we put real photos side by side: healthy grass, thatch, true dormancy, and the four problems we see most in Houston yards. Find the one that looks like yours.

The short answer

Green on top, brown bits down low, and still firmly rooted? That's thatch, and it's normal. Fading evenly across the whole lawn in December or January? It's going dormant. Let it rest.

Rings, patches, spots on the blades, or grass that pulls right up? Something else is going on. Keep reading.

Texas gardening legend Neil Sperry wrote a great piece on telling dormant grass from dead grass. Read it here.

The 30-second check

Before you panic, walk out to the brown area and do these three things. It takes less than a minute.

1
Look at the pattern
Green on top with brown flecks mixed in down low is thatch. An even fade across the whole lawn in December or January is dormancy. Rings, circles, or patches with a clear edge mean something else.
2
Give it a gentle tug
Grab a small handful and pull lightly. Dormant grass stays anchored. If blades slip right off the runner, or the grass lifts up with almost no roots, that's a problem.
3
Check the runners
Pull back the brown blades and look at the runners lying on the soil. Firm and green or white inside means alive. Dry, brittle and hollow means that spot is likely gone.

Want more tests? Our Houston lawn troubleshooter walks you through the tug, blade and soap tests step by step.

Stage 1Healthy

Healthy St. Augustine

This is what you're used to seeing from spring through early fall. It's your baseline for comparing everything below.

What it looks likeWide, flat, bright-to-deep green blades that stand up and grow thick enough that you can't see the soil.
When you see itSpring through early fall, while days are warm and the grass is actively growing.
The tug testFirmly anchored. The runners are plump and green, with plenty of white roots underneath.
What to doKeep doing what you're doing. Mow high, water deeply but not too often, and feed on schedule.

When to feed: Our free Texas Two-Step Lawn Method lays out exactly when to fertilize St. Augustine and Bermuda in Houston.

Stage 2Normal · What we're seeing now

Healthy green St. Augustine with brown, straw-colored old blades and stems visible at the base, typical fall thatch — Thatch: healthy green grass on top, with old brown blades and stems showing down low.

Healthy grass with thatch showing

This is what most of the November photos we get really show. The grass isn't dormant and it isn't sick. As growth slows, the new blades stop hiding the old ones underneath.

What it looks likeGreen, healthy blades on top with brown, straw-colored bits mixed in at the base. From a distance the lawn can look a little dull or speckled, but the growth on top is green.
When you see itFall, once St. Augustine slows down. Lawns that get a lot of nitrogen and water build thatch faster.
The quick testCut out a small wedge of grass with a knife or shovel and look at it from the side. The brown, spongy layer between the green blades and the soil is thatch. About a half inch or less is normal and even helpful. Over an inch is too much. Other warning signs: the lawn feels spongy when you walk on it, or the runners sit up off the soil.
What to doIf it's a normal amount, nothing. If it's building up, ease off the nitrogen and water, since those are what build it. Leaving your clippings on the lawn does not cause thatch.

Don't dethatch now. St. Augustine can't recover from it this late in the year. If you do have too much, wait until May or June, when the grass is growing hard. Use a vertical mower with the blades set about 3 inches apart, and make one pass in one direction only. Going at it too hard tears out the runners.

Stage 3Normal · Usually Dec–Jan

St. Augustine grass with green bases and tan, straw-colored blade tips as it goes dormant in fall — Going dormant: still green at the base, with tan tips. The color fades evenly across the lawn.

Going dormant (this is normal)

This is true dormancy. Here in Houston, St. Augustine usually doesn't get here until December or January.

What it looks likeGreen at the base, with tan or straw-colored tips. The color dulls evenly across the whole lawn instead of in spots. After the first frost, the top growth can turn completely straw-colored.
When you see itUsually December through February. St. Augustine slows down in the fall, but true dormancy comes when the soil stays below about 55°F, which usually means after our first freeze. That's typically in December, and later the closer you are to the coast. In a mild winter, St. Augustine may never go fully brown. It just dulls out.
The tug testStill firmly anchored. Pull back the blades and the runners are firm, with green or white inside.
What to doNothing dramatic. Follow the sleeping-lawn rules below and let it rest. It'll green back up in spring as the soil warms, usually around March or April.

One look-alike: If those tan tips look shredded or frayed instead of cleanly browned, your mower blade is probably dull. A sharp blade cuts clean. A dull one tears the tips and they brown out. Get it sharpened.

Fall & winter lawn rules

From now until spring, your lawn needs less from you, not more. Here's how to treat it right.

Put the fertilizer away. Pushing nitrogen to "green it up" now just feeds fungus. Wait for spring. The Texas Two-Step tells you when.
No weed-and-feed. Ever. Treat weeds and feed the lawn separately, at the right time for each.
Don't overwater. A slow or sleeping lawn needs very little. Only water if we go two to three weeks without rain, and do it in the morning. Wet grass overnight is how brown patch gets started.
Don't dethatch. St. Augustine can't heal from it before winter. If it needs it, do it in May or June.
Don't panic and rip it out. Wait for spring green-up to see what's truly dead. Most of it will come back.
Rake up the leaves. A blanket of wet leaves smothers St. Augustine and invites fungus.
Mow high, and only when it needs it, with a sharp blade. Don't scalp it.

When it's NOT just sleeping

These four problems are the ones we see most in Houston lawns. Each card shows what to look for and what to do.

Problem 1Needs action

A round patch of tan, thinning grass in a green St. Augustine lawn, typical of brown patch fungus — Brown patch: a round, tan patch that keeps getting bigger. The center can start greening back up.

Brown patch (large patch)

This is the #1 look-alike this time of year. Cool nights plus wet grass is exactly what this fungus loves.

What it looks likeRound or ring-shaped tan and yellow patches, from a couple of feet to several feet across. The outer edge is often orange-yellow, and the circles grow over time.
When you see itFall and spring, when nights are cool and the lawn stays damp. Overwatering, watering at night and fall fertilizing make it worse.
The quick testTug a blade at the edge of the patch. With brown patch, the blade slides right off the runner, and the base is dark and rotted.
What to doWater only in the morning, and only when needed. No nitrogen. Treat with a fungicide labeled for brown patch / large patch, and treat the green grass just outside the edge too.

Heads up: Treating stops it from spreading, but the brown spots won't green back up until spring. That's normal. The runners usually survive, so be patient.

Shop the Brown Patch Store →

Problem 2Act fast

St. Augustine lawn with irregular straw-colored patches in sunny areas near a flower bed, typical chinch bug damage — Chinch bugs: straw-colored patches in the sunniest, hottest parts of the yard.

Chinch bugs

Chinch bugs suck the life out of St. Augustine and can kill patches in just days. They're mostly a summer pest, but their damage is still showing up in a lot of fall photos.

What it looks likeIrregular yellow-to-straw patches that spread outward. They show up first in the hottest, sunniest spots, like along driveways, sidewalks and flower beds.
When you see itHot, dry weather, roughly late spring through early fall. In cool weather they slow way down, so brown spots that appear in November are more likely brown patch.
The quick testGet down at the edge where the dead grass meets the green. Part the grass with your fingers and look at the soil. Adults are about the size of a BB, black with white diamond-shaped marks on their wings. The babies are tiny and reddish.
What to doTreat right away with an insecticide labeled for chinch bugs. Grass they've killed won't come back, so plan to fix those spots in spring.

Fixing dead spots: Don't just throw down seed. St. Augustine can't be grown from seed. Scrape out the dead grass, loosen and improve the soil, then lay new sod tight in spring.

Shop the Chinch Bug Store →

Problem 3Needs action

Gray leaf spot

You have to look closely for this one. From the street the lawn just looks tired or scorched. Up close, the blades are covered in spots.

What it looks likeOval or diamond-shaped spots with gray or tan centers and dark brown to purple borders. Bad cases make the whole lawn look grayish and burnt.
When you see itHot, humid weather, mostly summer into early fall. It's worst on new sod, in shady spots, and on lawns that got too much nitrogen. It usually fades as the weather cools.
The quick testPick a few blades and look at them up close in good light. Spots right on the blade mean gray leaf spot. Brown patch rots the base of the blade instead.
What to doEase off the nitrogen during summer, water only in the morning, and treat with a fungicide labeled for gray leaf spot.

Shop the Gray Leaf Spot Store →

Problem 4Needs action

Take-all root rot

This one attacks the roots, so the top of the grass just slowly gives up. It's sneaky, and it often gets blamed on something else.

What it looks likeIrregular areas of yellowing, thinning grass with no clear edge. Over time the grass gets sparse and matted, and weeds move in.
When you see itIt gets going in cool, wet weather in fall and spring. The damage often shows up when heat arrives and the weakened roots can't keep up. Poor drainage, compacted soil and overwatering make it worse.
The quick testPull up a runner. Healthy roots are white. With take-all, the roots are short, dark and rotted, and the grass lifts up with almost no resistance.
What to doCut back the water and fix drainage. Topdress with sphagnum peat moss, and treat with a fungicide labeled for take-all root rot in fall and spring.

The ground underneath matters: Bad spots often trace back to compacted clay that was never amended. The grass isn't the problem. The foundation is.

Shop the Take-All Root Rot Store →

Cheat sheet: thatch, dormant or dead?

Here's the whole thing on one screen. Take a screenshot and bring it out to the yard.

What you see	Likely cause	What to do
Green on top, brown bits at the base, still anchored (fall)	Thatch	Normal. Check depth; dethatch only in May–June if over an inch
Whole lawn fading evenly, still anchored (usually Dec–Jan)	Going dormant	Normal. Let it rest.
Round tan rings that grow; blades slide off the runner	Brown patch	Morning watering only; fungicide
Straw patches in the hottest, sunniest spots, mostly in summer	Chinch bugs	Treat fast; resod dead spots in spring
Gray spots with dark borders on the blades	Gray leaf spot	Less nitrogen; fungicide
Thin, yellowing areas; short, dark roots	Take-all root rot	Fix drainage; peat moss; fungicide

Free download

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Questions we hear every fall

Is my St. Augustine already dormant in November?

Usually not. In Houston, St. Augustine slows down in the fall but typically doesn't go truly dormant until December or January, after the first freeze. The brown you see in November is usually thatch, meaning old blades and stems showing at the base of healthy grass.

Should I dethatch my lawn this fall?

No. St. Augustine can't recover before winter. Check the depth first. A half inch or less is normal. If it's over an inch, dethatch in May or June with a vertical mower set about 3 inches apart, making one pass in one direction only.

Will my dormant St. Augustine come back in spring?

Yes, as long as the runners are alive. Pull back the brown blades. If the runners are firm and green or white inside, it will green back up as the soil warms, usually around March or April.

Should I water a dormant lawn?

Very little. Only water if we go two to three weeks without rain, and water in the morning. Too much water on a sleeping lawn invites brown patch.

Should I fertilize to keep my lawn green this winter?

No. Nitrogen in fall and winter feeds brown patch more than it feeds your grass. Wait for spring. The Texas Two-Step Lawn Method tells you exactly when.

Can I overseed with ryegrass to keep it green?

We don't recommend it on St. Augustine. Ryegrass competes with your lawn when it's trying to wake up in spring. And St. Augustine itself can't be grown from seed, so bare spots get fixed with sod.

How do I tell brown patch from a dormant lawn?

Look at the pattern. Dormancy fades evenly across the whole lawn. Brown patch makes rings or circles that grow, and the blades at the edge slide right off the runner when you tug them.

When should I fix dead spots?

Wait until spring green-up so you can see what's truly gone. Then scrape out the dead grass, loosen and improve the soil, and lay new sod tight.

Still not sure what you're looking at?

Send us a photo. We look at Houston lawns every single day, and we'll help you figure out what's going on.

Ask a question (free) Book a call with Todd

More help: Houston Lawn Care Guide · Lawn Troubleshooter

Todd Farber

Aggie Horticulturist Todd Farber — Houston's Favorite · Garden Guy, serving Greater Houston since 1991

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Sabrina Farber https://www.garden-guy.com