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How to Grow St. Augustine Grass

By D.C. Winston ; Updated September 21, 2017
Shorn lawn grass.

St. Augustine is a warm-weather grass found in five different varietals that thrive in the subtropical humidity and warmth of the Southern United States. It has an identifiably coarse blade texture and spreads aggressively by over soil runners and stolons. It also has a distinctively bluish-green coloration and appreciates humidity and moisture but will tolerate occasional drought when well-established and mature.

Provide a full sun exposure for your St. Augustine grass. Partial daily shade that is lightly filtered or dappled can be tolerated well but full shade conditions will cause the grass to thin and become patchy.

Water your St. Augustine grass weekly with 1-inch of water to keep the deep blue green coloration and lush carpet effect. In cooler climates water once a week deeply and in warmer or drier climates split the waterings into two or more sessions each week. Your goal is to keep the soil evenly moist where the thatch and soil meet at all times. Once established it will survive drought but performance will be diminished.

Feed your St. Augustine grass twice a year with a granular lawn fertilizer formula. Make the first application in the early spring and the second mid-summer. Apply according to the manufacturers label directions and water in well. As an alternative to granular lawn food apply a general purpose liquid plant fertilizer diluted with water three to four times per growing season according to the label directions.

Mow your St. Augustine grass to the height you desire (generally 2-4 inches). Shorter can induce burn and longer reduces light to the lower blades. If your lawn becomes overgrown, never remove more than one-third of the blade length in one mowing session to reduce stress on the roots.

Dethatch at least once a year in the early spring or fall to help water and nutrients make their way to the lawn roots. St. Augustine builds a thicker thatch more readily than most other lawn grass varietals largely due to the width and thickness of its blades and stolons.


Things You Will Need

  • Water
  • Lawn fertilizer
  • Mower


  • Avoid herbicides and fertilizer products that contain 2,4-D as they can quickly kill St. Augustine grass. Look for products explicitly labeled for use on St. Augustine grass to prevent damage.