How to Grow and Care for St. Augustine Grass

Lawn of St. Augustine grass at a curbside.

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St. Augustine grass is also sometimes called "buffalo grass," although Bouteloua dactyloides is what people usually mean when they refer to the latter. St. Augustine grass is a spreading, warm-season grass used in lawns, especially in warm climates. It is a true grass, since it belongs to the Poaceae family. It can be distinguished from many other lawn grasses by its bluish-green leaves and by its low, creeping habit that allows it to form dense mats. It spreads via stolons. Its blades are wide and flat. A feature that you will love about St. Augustine grass if you live along the seacoast is that it is a salt-tolerant grass.

 Common Names St. Augustine grass, buffalo grass, carpet grass, couchgrass, quickgrass, wiregrass, mission grass, pimento grass, Charleston grass
 Botanical Name Stenotaphrum secundatum
 Family Poaceae
 Plant Type Herbaceous, perennial grass
 Mature Size 6 to 12 in. tall
 Sun Exposure Full sun to partial shade
 Soil Type Well-drained
 Soil pH 6 to 7.5
Hardiness Zones 7 to 12, USDA
 Native Area The Caribbean, South America, southeastern U.S. in the New World; Africa and Asia in the Old World

St. Augustine Grass Care


One of the great virtues of St. Augustine grass is that you don't have to mow it much, a fact that you will especially appreciate if you crave low maintenance. However, to achieve a lush lawn of St. Augustine grass, there is some work involved. You will have to keep up with the required irrigation and fertilization.

Light

Grow St. Augustine grass in full sun for best results, although it does tolerate some shade. In fact, of the warm-season grasses, it is the most shade-tolerant.

Soil

Provide St. Augustine grass with good drainage. A good garden loam works well.

Water

For best results, keep its soil evenly moist. St. Augustine grass is tolerant of a wide variety of soils and is moderately drought-tolerant once established, but it will perform best when you avoid either moisture extreme: too little or too much.

Temperature and Humidity

St. Augustine grass handles heat and humidity well, which is why it is popular in regions such as the American Southeast.

Fertilizer

St. Augustine grass performs best if fertilized regularly, on a schedule. Fertilize it initially in spring after it has finished greening up. During the summer, maintain a fertilizing schedule such that you feed it every 6 to 8 weeks. Any all-purpose grass fertilizer will be sufficient, but be careful to follow the application instructions on the package.

Types of St. Augustine Grass


There are a number of different types of St. Augustine grass. Examples include:

  • Floratine: offers narrower blades, for a finer texture
  • Floratam: a chinch bug resistant selection, but not as cold-tolerant
  • Seville: This selection offers both a finer texture and resistance to chinch bugs, but it also lacks cold tolerance.

Propagating St. Augustine Grass

St. Augustine grass has traditionally been propagated via sod (plugs), and it is in this form that turf farms or their retailers sell it to homeowners and landscapers. Since St. Augustine grass spreads so vigorously via its creeping stolons, it is easy to establish it from sod. In zones 7 to 12, you can start a lawn of St. Augustine grass any time during the growing season. Space the pieces of sod 1 to 2 feet apart and water faithfully. The grass grows fast enough to bridge the gaps during the first year.

How to Grow St. Augustine Grass From Seed

It is rare to grow St. Augustine grass from seed. But, if you are lucky enough to find the seed and want to try your hand at it, here is the information that you would need:

Sow the seed for St. Augustine grass in late spring to early summer. Sow 1/3 to 1/2 of a pound of the seed per 1,000 square feet. Pay special attention to keeping the ground evenly moist until you see that the grass has not only sprouted, but also begun to spread.

Overwintering

In all but the warmest climates in the U.S., such as the southern extremes of Florida and California, St. Augustine grass will turn brown in winter. As long as you are in at least zone 7, don't worry: It's not dead, just dormant. It will become green again when warm weather returns.

Common Problems With St. Augustine Grass

St. Augustine grass is prone to attacks from insects and diseases.

Chinch Bugs

St. Augustine grass is susceptible to infestations of chinch bugs. What makes these pests so deadly is that they do not merely eat your grass: They also inject a toxin into it. This toxin renders your grass unable to take up water properly, and the grass dies.

Prevention is the best way to control chinch bugs. Happily, the preventive measures required dovetail with the lawn care tasks you should be performing regularly (even if you don't fear a chinch bug infestation). Since you must eliminate dryness and thatch to ward off chinch bugs, simply make sure you:

  • Water as needed, especially during hot, dry spells.
  • Dethatch your lawn whenever you detect substantial thatch build-up.

Downy Mildew Disease

St. Augustine grass can be attacked by downy mildew disease. You can prevent downy mildew through good garden hygiene:

  • Poor air circulation promotes diseases such as downy mildew. They thrive in wet, humid environments. Aerate and dethatch your lawn as needed to foster better air circulation.
  • Water early in the day so that the grass blades have time to dry before nightfall.
  • Dig out and dispose of any diseased patches of sod as soon as you find them.
FAQ
  • How fast does St. Augustine grass grow?

    St. Augustine grass grows more quickly than do many other lawn grasses.

  • What are some other benefits of St. Augustine Grass?

    Because it forms such dense mats, it is successful at crowding out weeds.

  • Is there a downside to growing St. Augustine Grass?

    Yes. It doesn't hold up to foot traffic as well as some warm-season grasses do.