If you want the perfect lawn, you have to choose a grass that is appropriate for your region. If you’re thinking about planting St. Augustine grass, you’ve got to live in a warm weather grass region. In this in-depth guide to St. Augustine Grass, I’ll share everything you need to know about St. Augustine grass and how to decide whether it’s the right fit for you and your lawn.
St. Augustine grass thrives in subtropical coastal regions. It’s a warm-season grass that grows best during the high heat of summer, but it is notable for its cold and drought tolerance.
When it grows in its ideal conditions, St. Augustine creates a beautiful, dense carpet of coarse, textured grass.
History of St. Augustine Grass
St. Augustine grass is unique to lawn grasses found in the United States because it is native to the area. It’s native to the Gulf of Mexico and West Indies, though it’s found largely around the Atlantic ring.
This grass is now found along the northeastern coast of Brazil, as well as along the western coast of Africa.
Records from explorers in the late 1700s noted St. Augustine growing in those nations. Nowadays, St. Augustine is found across the whole of the United States.
Residents have spread the grass into a wider region, bringing it to Australia, California, Rhodesia, Senegal, and the Congo. It was introduced to Hawaii by 1816, and it was brought to Australia and New Zealand by the 1840s.
St. Augustine grass was in steady use as a lawn grass in Florida by the 1890s, and in California by the 1920s.
Growing St. Augustine Grass in Your Yard
St. Augustine grass is found largely in coastal regions, and specifically along the American Gulf Coast. It’s also highly tolerant of salt, which makes it perfect for that area.
This grass spreads aggressively with above-ground stolons. It requires moderate maintenance.
With St. Augustine, you get a thick carpet of grass that creates an impressive appearance and helps with forcing out weeds. It performs best when left longer, at about 3 to 4 inches.
You should water it regularly but not excessively. The grass will grow well if you keep it moist throughout the warm season.
St. Augustine grass is a coarse-textured grass. It is dark green in color with thick, flat grass blades and is one of the best performing warm-season grasses.
It has an incredibly quick spread and is a stoloniferous grass species, spreading via stolons above ground, rather than rhizomes (which spread laterally below ground).
In the above photo you can see the lateral green shoots of St. Augustine stolons which branch off to create a new plant which sets down roots and sends out its own stolons to spread laterally.
This growth habit makes St. Augustine self-repairing and it will naturally grow thick and dense to crowd out weeds.
Peak Season for St. Augustine Grass
The peak season for St. Augustine grass is during the summer months while temperatures stay between 75 degrees and 90 degrees Fahrenheit.
It has comparatively high drought tolerance and maintains a deep green color longer than other warm-season grasses.
However, St. Augustine does go dormant during drought season. Its tolerance for the cold behaves similarly.
St. Augustine grass maintains its green color longer than other warm season grasses, though it cannot withstand extended cold periods.
Optimal Soil and Lawn Conditions
St. Augustine grass is highly resilient, able to grow in adverse conditions. It does well in acidic soils with pH levels between 5.0 and 8.5.
Its salt tolerance is amongst the highest of the warm season grasses, and it grows well in sandy soil.
An established St. Augustine lawn has a high tolerance to shade, but newly planted grass won’t grow well in those conditions.
New grass growing in shady conditions will grow in thin and spindly, and you won’t end up with the thick St. Augustine lawn that you want.
St. Augustine needs 4 to 6 hours of sun to grow best. During the cool season, St. Augustine grass goes dormant and will turn brown until spring.
Common Issues with St. Augustine Grass
St. Augustine grass requires water and regular fertilizer to grow to its potential. It needs moderate maintenance throughout the season and will turn brown during the colder months.
While St. Augustine can handle an average level of foot traffic, it cannot withstand heavy traffic. That is why it’s inappropriate for sports fields and well-trodden walkways.
St. Augustine is also highly vulnerable to pests. The southern chinch bug is its biggest threat, as this insect can quickly destroy a St. Augustine lawn.
Fortunately, the southern chinch bug can be easily controlled when caught early. They do not fly, which makes infestations easier to control.
St. Augustine is also susceptible to diseases, such as leaf spot or lawn patch. However, its thick, coarse texture allows it to withstand diseases better than other warm season grasses.
Types of St. Augustine Grass
St. Augustine grass has been an established lawn grass in the United States.
It has multiple cultivars available that are developed for different strengths.
Released in 2007, Captiva is one of the newer St. Augustine cultivars. It has a darker green color with short, narrow blades.
It grows more slowly than other cultivars and is known as a “dwarf cultivar” because it should be mowed to the lower height of 2 to 2 ½ inches.
Captiva has increased tolerance to shade and chinch bugs. However, it’s susceptible to fungal diseases when over-fertilized.
This is a cultivar developed in the early 1970s for its increased disease resistance and resistance to chinch bugs.
Floratam has since become the most St. Augustine common variety in Florida. It is easy to care for and is the most drought tolerant of the cultivars.
This is another dwarf cultivar that grows in short internodes and has a dark green color. It has good cold tolerance and does well in both shade and full sun.
It is susceptible to pests, like chinch bugs and sod webworms, as well as fungal diseases.
The Palmetto cultivar is known for its brighter, emerald green color. It has a slightly finer texture than we see with regular St. Augustine grass, and it exhibits additional cold, heat, shade, and drought tolerance.
However, Palmetto grasses have added susceptibility to fungal diseases, especially in the colder winter months.
This cultivar has a medium-green color and a coarser texture. Raleigh has increased cold tolerance but lower heat tolerance, as it will turn yellow and go dormant during peak temperatures.
Raleigh requires additional acidity, which can lower the extent that it yellows. It is susceptible to fungal diseases and chinch bugs.
Sapphire is one of the premium St. Augustine cultivars, offering more aggressive growth and a rich blue-green color.
It recovers from damage quickly, and it’s heat and drought tolerant. However, Sapphire has a high susceptibility to fungal diseases and requires added maintenance to keep it healthy.
This is a much finer textured cultivar of St. Augustine. Seville has a lovely blue-green color that stays vivid well throughout the year.
It has added shade tolerance and extra resistance to pH levels in the soil. Seville can thrive in a wider range of conditions and requires comparatively less maintenance than other kinds of St. Augustine grass.
Bitter Blue is one of the older cultivars of St. Augustine grass. It was developed in the 1930s.
Bitter Blue is a dark, blue-green color with a fine, dense texture.
This cultivate is adapted for wide use and has good tolerance to cold and shade. It requires a higher mowing height at 3 ½ to 4 inches.
Despite its name, Classic is a relatively recent cultivar. It was released in the early 2000s.
This cultivar has good cold tolerance and needs to be mowed higher at a height of 3 ½ to 4 inches.
This is another recent cultivar, released in 2005. It has good cold tolerance and shade tolerance, though it doesn’t have the highest tolerances of other cultivars.
Delta Shade has a lighter shade of green and requires a higher mowing height at 3 ½ to 4 inches.
The Best Time to Plant St. Augustine Grass
As a warm season grass, St. Augustine is best planted during the spring or early summer. It prefers warmer weather and grows best when temperatures are at least 75-degrees Fahrenheit.
It’s best to plant it during warm weather. Make sure to plant your St. Augustine lawn when the weather is warm but before the dry season sets in and at least 3 months before the year’s first frost.
St. Augustine grows quickly and takes usually 1 to 2 weeks for the roots to establish in your yard.
You’ll probably have to use plugs or sod if you want to plant a St. Augustine lawn. Most cultivars of St. Augustine aren’t available as seed.
I don’t recommend overseeding with this grass. Overseeding is simply unnecessary in most cases, as it grows so aggressively, and will self-repair through stolons.
Planting St. Augustine Grass from Plugs
Planting St. Augustine from plugs will take about one year for a full lawn to develop, but it’s also a less expensive option than buying sod.
You can order trays of plugs online from Amazon or directly from sod growers, and you’ll want to plant your plugs 12″ apart for a lawn that establishes itself in a single season. If you’re more patient, you can plant plugs 24″ apart and cut your cost in half.
Preparing Your Lawn
The first thing to do is measure your lawn and determine the dimensions of the area that you want to cover. I have a free lawn measuring tool to calculate the square footage of your yard to use for this:
You will need 18 plugs for every 32 square feet of lawn.
If you still have any lawn in the area, use a sod-cutter or tiller to remove the existing grass.
After that, you should apply herbicide to kill any weeds. Let it sit for 2 weeks (this timing may vary depending upon what you use) so the herbicide dissipates and you won’t kill your new grass.
You can hand pull small amounts of weeds. Fully dig out the roots, otherwise the weeds will return while the new grass establishes itself.
Water extensively before you plant the plugs, so that the ground is wet. The soil should be soaked but there shouldn’t be so much moisture that it starts pooling at the surface.
I recommend placing your plugs in diagonal patterns across the yard. You should space out the holes so there is about 12 inches between them.
Dig the holes slightly wider than the plug, but only as deep as the plug.
Get a grass plugging tool (like this one on Amazon) to do this task. It’ll make it easier to dig plug-sized holes, and will keep you off your hands and knees.
You want the plug to be flush with the ground, otherwise it will be uneven. If you accidentally made the holes too deep, you can easily fix that problem by adding back some soil at the bottom to fill in the space.
Water every day until the roots have established themselves, which usually takes about 1 to 2 weeks. When you see the grass start spreading in your yard, you’ll know that the roots are established.
At this point, you can cut down the watering to once a week. Take any heavy rainfall into account.
Planting from Sod
Laying sod is a much easier method for planting St. Augustine grass. You get an instant lawn!
If your lawn has a lot of shade, laying sod is the best option. It’s a lot more expensive than using plugs, but you’re paying for the speed and convenience of getting a perfect lawn right away.
You can hire a landscaping company to install your sod for you, but if you want to save a few bucks and DIY the job, here’s how:
How to plant your St. Augustine lawn from sod, step by step
Step 1: Remove Old Lawn and Use Herbicide
If you have any old lawn, you need to remove it. Use a sod cutter or till your lawn.
After that, use herbicide to remove any weeds and then wait two weeks.
Step 2: Roll Out the Sod
Once you’ve waited two weeks after removing old lawn and applying herbicide, it’s time to roll out the sod.
Water the soil to get it ready for the sod. Then, begin by rolling out the first piece.
Press the sod lightly into the ground. Match the next piece end to end and roll it out. Then blend the edges together using your hands.
When you begin to roll out the next row, cut the first roll in half and lay each half at the opposite ends of the row.
The sod should be laid out in the same pattern you see in bricks. This strengthens the grass as it grows.
Step 3: Water Daily
Water daily until the roots establish themselves in the yard. Once established, you can reduce to watering once per week.
St. Augustine Grass Maintenance
Here’s how you maintain your new St. Augustine lawn.
Proper maintenance is the most important part of keeping your St. Augustine lawn healthy and beautiful.
St. Augustine needs one inch of water per week, with increased amounts during the warmer months. Be careful to keep your lawn wet throughout the season, otherwise it will dry out and turn brown.
Keep adding water as long as the ground absorbs the moisture. You don’t want it to pool, otherwise you increase the risk of fungal diseases.
Apply water early in the morning. That’s the best time for it to fully absorb into the ground.
If you wait until the hot part of the day to water, the moisture will evaporate before it fully absorbs into the ground. That means your grass won’t get the hydration it needs.
Don’t water at night, either. The ground will stay too moist and put your lawn at risk of fungal diseases.
St. Augustine requires regular fertilization to maintain a green color. Conduct a soil test prior to applying fertilizer to know what your lawn needs.
St. Augustine requires acidic soil and may require applications of a product to lower the pH level if it is too alkaline. I recommend Mag-I-Cal Plus from Jonathan Green for this.
Fertilizer should be applied during the middle part of the season. It’s important that the roots be well-established before you apply fertilizer, so don’t do it too early.
Also, you shouldn’t apply fertilizer after the growth has subsided late in the year.
St. Augustine requires a lot of nitrogen throughout the year. It requires 4 to 5 pounds per 1,000-square-feet per year, best applied through infrequent uses of high-nitrogen fertilizers.
Be careful not to apply too much fertilizer throughout the year. That causes thatch to develop and creates a higher risk of disease.
If thatch becomes an issue, you can remove it using a hard rake. However, it’s best to remove it early in the season so that it repairs itself before going dormant.
It’s best to allow St. Augustine to grow higher than most other warm-season grasses. I recommend maintaining it at a mowing height of 3 ½ inches to 4 inches.
A higher grass height helps it retain tolerance to drought and cold.
It should be mowed higher throughout the summer and lower in the winter. Do not mow it to a height less than 3 inches.
Mow every 1 to 2 weeks, depending on the height of the grass. Mow regularly enough that you only remove the top third of the blade and leave the clippings to provide a little bit of nitrogen week to week.
Final Thoughts About St. Augustine Grass
St. Augustine is a beautiful lawn grass that is in southern coastal regions.
It requires a moderate amount of maintenance, but when grown in the proper climate, it is easy to maintain and has better tolerances to salt, shade, and cold than other warm season grasses.
This grass features a coarse texture and dark green color that will make your yard stand out with its gorgeous hues.
There are about a dozen cultivars available that can suit it to your yard’s unique conditions.
Its thick growth habit allows it to easily crowd out any weeds. When it’s well maintained, it is very durable and can withstand health issues better than most other warm season grasses, which can be prone to disease and pest problems.