How to Care for St. Augustine Grass in Florida

St. Augustine is the most popular turfgrass in Florida for good reason—it’s perfectly suited to the climate. However, even the most ideal grass needs the proper care. To care for St. Augustine in Florida, follow these rules:

• Plant St. Augustine sod and soil plugs in spring (February–March).
• Water deeply 2 times per week during the growing season.
• Fertilize 2–6 times per year, with fertilizer applications evenly spaced from spring through fall.
• Mow at a height of 3 inches.
• Aerate in spring, prior to your first application of fertilizer.

In Central and North Florida, including Orlando, Jacksonville, and Tallahassee, St. Augustine will go dormant in the winter. Dormant grass does not need fertilizer or mowing, so your lawn care routine will change with the seasons. In South Florida, from Tampa Bay down to Miami, St. Augustine may stay green all year round. This requires a year-round fertilizer and mowing routine.

Best Time to Plant St. Augustine Grass in Florida

The optimal time to plant St. Augustine in the northern and central regions of Florida is in Spring, as the grass begins to green up. In southern regions, such as Miami and Ft. Lauderdale, St. Augustine grass can be established at any time of year, because it grows year-round.

• Early spring (February–March) is the best time to plant St. Augustine in Florida.
• In northern regions of Florida (Tallahassee, Jacksonville), adhere closely to this spring schedule.
• In South Florida (Miami, Ft. Lauderdale) St. Augustine can be planted year-round.
• St. Augustine cannot be established with seed. Lay sod or use grass plugs.

St. Augustine does not grow well from seed, so you will need to choose whether to lay a new sod lawn or establish your yard with evenly spaced “plugs” of St. Augustine. St. Augustine spreads quickly via stolons (runners) so a lawn started with plugs can become a thick lawn within a growing season.

How Often to Water St. Augustine Grass in Florida

Watering your St. Augustine depends on two things—soil type and time of year. If your lawn is primarily sandy soil, it will not retain water, so you’ll have to water more frequently. If you have clay soil, the ground will hold water and require less frequent watering. Similarly, St. Augustine needs more water during the summer growing period and less water during winter.

• Clay Soil: Water 2 times per week with 0.75 inches of water each session (30–45 minutes with a sprinkler).
• Sandy Soil: Water 3–4 times per week with 0.75 inches of water each session (30–45 minutes with a sprinkler).
• In winter, during reduced grass growth or dormancy, reduce watering to 1 session every 2–4 weeks. If you receive at least 1 inch of precipitation during this period, watering is unnecessary.
• Monitor your lawn. Underwatering can cause drought stress and invite chinch bugs.

When Florida storms roll in, subtract any natural precipitation from your lawn’s watering needs. In order to save money and prevent overwatering your lawn, it’s best to invest in a programmable irrigation system. This wi-fi enabled sprinkler controller allows you to change watering times from your phone.

Best Time to Water St. Augustine Grass in Florida

It’s always best to water your St. Augustine early in the morning before the sun has risen to its peak. Because of Florida’s hot days, watering in the afternoon can cause water evaporation that deprives your lawn of moisture.

• Water in the early morning (5–7 AM) for best results.
• Avoid watering in the evening. This leaves standing water overnight and encourages grass disease, mold, and attracts pest insects.

Watering in the evening contributes to standing water on your lawn. Add that to Florida humidity and you have the perfect recipe for grass mold and disease. To avoid these dangers, set a timer for your sprinkler system so that watering begins just before sunrise.

When to Fertilize St. Augustine Grass in Florida

In South Florida, where St. Augustine does not enter dormancy, you can fertilize year-round, typically once every 60 days. In Central and Northern Florida, from Orlando through the panhandle, plan to fertilize 4 times, with the first application in February, and the last application in October.

• St. Augustine typically requires 2–6 applications of fertilizer per year.
• In South Florida, fertilize once every 60 days.
• In Central and Northern Florida, fertilize 4 times: in February, April, July, and October.

St. Augustine requires 2–4 pounds of nitrogen per 1,000 square feet of lawn annually. This makes it a rather nutrient-hungry grass. In order to keep your lawn lush and green, meet these nitrogen needs. A healthy St. Augustine lawn will drive out weeds and resist disease.

Best Fertilizer for St. Augustine Grass in Florida

St. Augustine needs more than just one type of fertilizer. A gentle, iron-rich fertilizer applied in early spring promotes the blue-green color St. Augustine is prized for without compromising root growth. While a more powerful fertilizer used during late spring and fall months gives a massive growth boost, encouraging St. Augustine to heal from damage and crowd out weeds.

• Use a gentle fertilizer, like Milorganite, during spring green-up and peak summer months.
• During late spring and fall applications, use a more powerful fertilizer for warm-season grasses.
• See our guide on hybrid fertilization programs for more information on fertilizer types and timing.

If your lawn seems dry after an application of strong fertilizer, increase the duration of your watering sessions. Strong fertilizers can pull moisture from the soil. Monitor your grass for fertilizer burn in the 2 weeks following fertilizer application.

Best Weed and feed for St. Augustine Grass in Florida

Weed and feed products with 2,4-D, Dicamba, and/or Mecoprop are ideal for St. Augustine. All of these weed killers are safe for use on St. Augustine. A high-quality weed and feed for St. Augustine will combine 2 or more of these active ingredients.

• Choose a product that combines at least 2 of the following ingredients: 2,4-D, Dicamba, Mecoprop.
• Replace a late spring fertilizer application with this weed and feed to fertilize your lawn and kill weeds at the same time.
• If your lawn suffers from broadleaf weeds in winter, replace a fall fertilizer application with weed and feed.

The best thing about weed and feed is that it provides fertilizer at the same time it kills broadleaf weeds in your lawn. Just remember that if you are using weed and feed, swap it out for a fertilizer application. Do not apply both fertilizer and weed feed. This can overload your lawn with fertilizer and damage your St. Augustine grass.

How High to Cut St. Augustine Grass in Florida

St. Augustine thrives best when cut to 3–4 inches in height. This allows St. Augustine to become a thick, weed-preventing ground cover. St. Augustine grass cut too short will look sparse and leave exposed soil where weeds can take root.

• When St. Augustine is green and growing, mow grass to 3–4 inches in height.
• Mow higher (4 inches) if you are battling weeds. Longer grass will shade weeds and crowd them out.
• Never mow dormant (brown) St. Augustine. This can damage or kill the grass.

In North Florida, where St. Augustine enters winter dormancy, do not mow in winter. Once the grass greens up, mow at a height of 2.5 inches through April. This will help get rid of dead growth. In May, raise mowing height to 3–4 inches and continue to mow at this height until grass goes dormant in winter.

When to Aerate St. Augustine Grass in Florida

Florida St. Augustine lawns benefit from aeration in February–March. This spring aerification reduces thatch buildup, allows fertilizer to penetrate the ground, and loosens the soil to promote root growth.

• Aerate in early spring (February–March).
• Aerate before your first fertilizer application. The aerated ground absorbs fertilizer more efficiently.

By breaking up thatch through aeration, you encourage better grass growth and reduce the risk of grass disease and invasive insects. It’s important to test your lawn each spring to determine if it’s in need of aeration.

How to Take Care of St. Augustine Grass in Florida

Keep chinch bugs and disease out of your St. Augustine lawn by promoting healthy grass growth. This requires planting new St. Augustine in spring, mowing at 3–4 inches in height, deep watering to promote root growth, fertilizing 2–6 times per year, and spring aeration to keep compacted soil from choking the life out of your grass.

By taking these steps to ensure the health of your lawn, your St. Augustine will not only be completely free of disease, pests, and brown patches, it will also save you money in the long run. Because St. Augustine can’t be replaced by seed, repairing dead grass requires installing sod or soil plugs. Rather than replant, it’s easier to care for St. Augustine in Florida and reap the benefits of a beautiful, weed-free lawn.