8 Methods to Reviving St. Augustine Grass

By: Ken Wilson

St. Augustine grass is a beloved perennial turf option found in temperate climates throughout the Southern United States and Central America. Due to its poor winter hardiness, St. Augustine grass turns brown during colder seasons. Fortunately, with a few tricks, you can revive St. Augustine grass to its former glory.

The best way to revive St. Augustine grass is to water it with 1 to 1½ inches weekly. Ensure you provide sufficient nitrogen fertilizer and only mow the lawn when it reaches 3 inches tall. Prioritize treating lawn diseases, pests, and weeds. Re-sod the lawn if the grass has died.

Is your St. Augustine lawn starting to look lackluster? With a few changes in your garden routine, you can revive your lawn to a dense carpet of lush grass that will have the neighbors green with envy.

How to Bring Back Dead St. Augustine Grass

After establishing a St. Augustine grass lawn, the success will largely depend on management. Without proper care, it can develop unsightly brown patches.

The primary reasons your St. Augustine grass is suffering include turf diseases, pests, poor soil quality, and excessive fertilization. While you cannot revive truly dead grass, you can restore your lawn if there are brown, thin, patchy areas.

Here’s how.

1. Water Your Lawn Correctly

Ensure you follow the correct watering schedule to revive and keep your St. Augustine lawn healthy. During dormancy, water your lawn to prevent drought stress, excessive dehydration, and turf loss. St. Augustine grass typically thrives in soil with a moist six-inch top layer. The deep moisture boosts root establishment and downward root growth. You can test the moisture depth using a soil probe or wood stake.

After wetting the soil six inches deep, refrain from watering until the grass on the lawn boasts symptoms of drought stress – bluish-gray or white cast color, folded leaves, and footprints. During the growing season, provide ¾ to 1 inch of water when the lawn appears dry.

Then wait to irrigate the grass until the lawn shows drought stress. St. Augustine grass typically requires watering every 5 to 10 days during the growing season.

2. Mow Your St. Augustine Lawn On A High Setting

Mow St. Augustine grass routinely once it turns green during spring, but avoid removing more than one-third of the leaf area each time you mow. Mowing St. Augustine grass too short can damage the lawn by depleting the grass’s energy reserves.

If the lawn is repeatedly cut too short – scalped – it can starve the grass and give it a yellow-brown appearance. Set your mower to 2½ to 3 inches and 3 to 3½ in shaded areas to keep your St. Augustine grass healthy.

Pro tip: Ensure your lawn mower has sharp blades to cleanly cut through the grass. Dull mower blades can tear the grass, leaving frayed edges vulnerable to disease.

3. Dethatch & Aerate the Lawn

If the thatch layer – the intermingling of undecomposed plant matter – is too thick, it becomes impenetrable. This prevents the grass from absorbing sufficient nutrients, water, and oxygen. So dethatch your lawn once the thatch becomes thicker than ¾ inches.

Eliminate compacted soil in high-traffic areas using aeration. Aeration will encourage a dense root system, which can nourish the grass through long, hot summers. St. Augustine grass is best aerated in its growing season, from mid-spring through summer. Aerating the grass while actively growing ensures optimal conditions for a speedy recovery.

4. Treat Any Existing Lawn Diseases

St. Augustine grass is susceptible to numerous turf diseases. This type of turf grass is particularly susceptible to common lawn diseases, especially when vulnerable and exposed to excessive moisture. Most fungal and bacterial diseases that affect St. Augustine include:

  • St. Augustine Decline (SAD): Chlorotic mottling or stippling of leaves.
  • Pythium root rot: Nondistinctive, irregular yellow or brown patches. (Treatment: Fungicides)
  • Brown patch disease: Large patches in the lawn turn from yellow to reddish-brown, then brown to straw-colored. (Treatment: Fungicides)
  • Gray leaf spot: Small brown spots that expand into large, oval gray leaf spots, surrounded by purplish-brown borders. Cottony fungal growth can form during warm weather. (Treatment: Fungicides)
  • Helminthosporium leaf spot: Tiny (pinhead size) solid purple or brown spots that expanded into lesions with bleached centers on the leaf blade. (Treatment: Fungicides)

5. Get Rid of Pests

White Grubs, Chinch Bugs, and Ground Pearls are the most common insect pests affecting St. Augustine grass lawns. For the fastest solution, use curative chemicals like trichlorfon and carbaryl to kill white grubs and chinch bugs. Consider calling the local lawn pest control to help clear the infestation.

6. Prioritize Weed Control

A healthy St. Augustine lawn crowds out most weeds. However, broadleaved and grassy weeds can easily invade a poorly maintained or infested St. Augustine lawn.

Broadleaf weeds like chickweed, henbit, and clover mostly invade dormant St. Augustine grass. And the most common grassy weeds that emerge include crabgrass, fescue, and annual bluegrass. Maintaining a dense, healthy lawn is the first step to weed control. Ensure you perform regular maintenance like mowing, irrigation, and fertilizing to promote healthy growth.

Pro tip: Bag up those grass clippings. Even though the clippings can provide nutrition to your lawn, it increases the likelihood of weed seed heads sprouting in your lawn.

You can also control weeds by using preemergence herbicides in the spring once soil temperatures reach 65 degrees Fahrenheit and applying post-emergent herbicides after weeds have sprouted as needed.

7. Rethink Your Fertilizer Application

You may want to rethink your fertilizer application if your St. Augustine is growing a bit spindly. A lot of the sandy soil in the coastal areas needs more nutrients to ensure the turf reaches its full, lush potential.

Fertilize St. Augustine grass during the summer growing season. It’s best to first conduct a soil test to determine the pH and lacking nutrients to select the best fertilizer. If you skip this step, opt for a complete fertilizer with a 3-1-2 nitrogen, phosphorus, and potassium ratio.

The Texas A&M University System recommends applying 1½ pounds of slow-release nitrogen fertilizer per 1,000 square feet every 10 weeks or 1 pound of soluble nitrogen fertilizer every 8 weeks. Over-fertilization and excess nitrogen can damage your grass roots and cause fertilizer burn. To revive your St. Augustine lawn, flush out the extra salt with a generous amount of water. Soak the yellowing and browning areas with 1 inch of water daily for a week to reduce fertilizer burn.

8. Re-Sod Your Lawn

Extensive lawn damage may be beyond repair. If so, the best way to revive your St. Augustine grass is to re-sod your lawn. Sodding your lawn will remove patchy spots, minimize weed growth, reduce soil erosion, and give your lawn much-desired aesthetic appeal.

Final Thoughts

With that, the success of your St. Augustine grass lawn depends largely on management. You can easily revive your St. Augustine grass lawn with a consistent watering, mowing, and fertilizer schedule. Ensure you prioritize weed control and treating any existing diseases and pests! (Related article: 6 Steps to Caring for St Augustine Grass so it Grows Lush)

About the author 

Ken Wilson

Long time career in the home services industry from remodeling to patio construction. Currently residing to in SWFL and active contributor to multiple home & garden publications.