Cut your lawn on the tall side. In Central Texas, most warm-season grasses do best at 2.5 to 4 inches, and the exact number depends on the type of grass you have. St. Augustine wants to stay tall, Bermuda likes it shorter, and Zoysia and buffalo fall somewhere in between.
The reason is simple. Taller grass shades the soil, keeps roots cooler, holds moisture longer, and blocks sunlight from reaching weed seeds. In our heat, with clay soil that bakes hard and long dry spells between storms, that shade is one of the cheapest tools you have for a healthy lawn.
What is the right mowing height for each grass type?
Set your mower by the grass you actually have, because each one has a different comfort zone. Here’s where to keep them in Central Texas:
- St. Augustine: 3 to 4 inches. This is the most common lawn grass around Austin and San Antonio, and it wants to stay tall. It spreads with runners that sit on the soil surface, so a low cut shaves off its growing points.
- Bermuda: 1.5 to 2.5 inches. Bermuda is the exception. It’s built to take a shorter cut and actually gets thicker and denser when you keep it low and mow often.
- Zoysia: 1.5 to 2.5 inches. Zoysia is slow and dense. Keep it in the low-to-middle range and it forms a tight, carpet-like turf.
- Buffalo grass: 3 to 4 inches, or leave it unmowed. Buffalo is a native, drought-tough grass. It’s happy tall and only needs cutting every few weeks, which makes it a favorite for low-water yards.
If you’re not sure what you have, St. Augustine has wide, coarse blades and rolls out in thick mats, while Bermuda has fine blades and a low, wiry growth habit. Texas A&M’s AggieTurf has a grass identification guide that walks you through the differences.
What is the one-third rule and why does it matter?
Never cut off more than one-third of the grass blade in a single mowing. That’s the one-third rule, and it’s the single most important habit for a healthy lawn. If your St. Augustine is sitting at 3 inches and you want it at 3 inches, you mow when it reaches about 4.5 inches, taking off an inch and a half.
When you break that rule and scalp the lawn, you shock the plant. It has to pour energy into growing new leaves instead of deep roots, and the exposed soil dries out and heats up. Texas A&M AgriLife Extension points to consistent, moderate mowing as one of the foundations of a low-maintenance lawn. In practice, the one-third rule means you mow more often when the grass is growing fast in late spring and early summer, and less often once the real heat slows things down.
Why does mowing tall help in the Central Texas heat?
Tall grass protects itself and your water bill. A longer blade means a bigger solar panel feeding the plant, and it casts shade that keeps the soil surface several degrees cooler. Cooler soil loses less water to evaporation, so the lawn stays green longer between waterings. That matters here, where summer watering restrictions in Austin, San Antonio, and the surrounding towns limit how often you can run the sprinklers.
That shade does double duty against weeds. Crabgrass, sandburs, and most other weed seeds need sunlight hitting bare soil to sprout. When your grass is tall enough to shade the ground, a lot of those seeds never get the light they need. A thick, tall stand of St. Augustine or buffalo is one of the best weed barriers you can grow, and it costs nothing extra. If your lawn is thin and letting weeds through, our lawn maintenance crew can get it back on a mowing schedule that thickens it up.
Keeping the lawn tall also pairs well with smart watering. Deep, infrequent watering drives roots down, and tall top growth keeps that moisture from cooking off. If your sprinklers are uneven or running too often, an irrigation tune-up will stretch every gallon further.
Is scalping ever a good idea?
Scalping on purpose is a myth for most home lawns, so skip it. Some folks scalp Bermuda or Zoysia low in early spring to clear out dead thatch and help the soil warm up faster, and for those two grasses, done once and done carefully, it can work. But scalping St. Augustine or buffalo grass just damages them, and scalping any lawn in the middle of summer is asking for trouble.
The other scalping myth is that a shorter cut means you mow less often. It’s the reverse. A scalped lawn is stressed, thin, and full of gaps, so weeds move in and you spend the season fighting them. A lawn mowed tall and on schedule grows a little slower up top and crowds weeds out on its own. Sharp mower blades matter too, because a dull blade tears the grass and leaves ragged brown tips that look like scalping even when your height is right.
How often should you mow through the year?
Mow based on growth, not the calendar. In the fast-growing stretch from April through June, that often means every five to seven days. Once July and August heat sets in and the grass slows, you may drop to every 10 to 14 days. Come fall, growth picks back up briefly, then tapers off for winter.
Watch the grass, not the day of the week. As long as you’re following the one-third rule and keeping your blades sharp, you’ll land on the right schedule for your yard. Homeowners in Austin and the surrounding towns deal with the same heat and soil, so these numbers hold across the corridor.
Want your lawn cut at the right height, on the right schedule, without the guesswork? Corral Bros handles lawn mowing across the Austin to San Antonio corridor. Get a free quote or call us at (737) 404-9343.