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How to Plant, Grow, and Care for St. Augustine Grass

By: Melissa Pino Published: 4 Jul, 23 Updated: 6 Aug, 23

St. Augustine grass is a popular choice for many homeowners and landscapers, especially in warm climates like Florida and the Gulf States.

Known for its vivid green color and natural density, this grass variety creates beautiful lawns that are both heat and humidity tolerant. Its salt tolerance also makes it an excellent option for coastal yards.

This type of grass is a staple in southern home lawns. It has coarse, tropical-looking blades, thrives in warm or humid environments, and can be quite stress resistant in some situations.

This low, creeping grass forms dense mats as it spreads through stolons. With proper care, gardens and yards can benefit from its resilience and adaptability to various soil types, as long as they are well-drained.

But what is it about this type of grass that makes it so appealing to homeowners? If you’re looking to install a new lawn and are thinking about St. Augustine, this article is perfect for you!

I’ve been growing St. Augustine grass for many years as a master gardener in Texas, and in this article, I’ll share everything you need to know about St. Augustine grass including its key characteristics, care guide, and how to plant it properly.

Photo Credit: Shutterstock.

Botanical Name: Stenotaphrum secundatum

Common Name: St. Augustine grass, carpet grass, couchgrass, buffalo grass, quickgrass, wiregrass, mission grass, pimento grass, Charleston grass

Family: Poaceae

Plant Type: Herbaceous, perennial

Hardiness Zones: 7 – 12 (USDA)

Sun Exposure: Full sun to partial shade

Soil Type: Well-drained

Soil pH: Acidic, neutral, alkaline

Native Area: North America, South America, Caribbean, Africa, Asia

Understanding St. Augustine Grass

Before we jump into planting and caring for your St. Augustine grass, it’s important to understand the characteristics of this grass.

Native to tropical and subtropical regions, St. Augustine grass prefers warm temperatures and high humidity and is known to have a good shade tolerance. Its ideal growing range is from Texas and Florida, down to the Caribbean and South America.

Characteristics of St. Augustine Grass

St. Augustine grass has a coarser texture than most other lawn grasses, and its grass blades can grow up to 10 inches long. It’s a creeping grass, meaning it spreads through above-ground stolons and below-ground rhizomes. Its root system runs deep, making it drought-tolerant, but also making it more difficult to transplant once established.

One of the most unique characteristics of St. Augustine grass is its ability to grow in shade. While most grasses require full sun, St. Augustine grass can tolerate moderate to heavy shade, making it a great choice for lawns with lots of trees or buildings that block out the sun.

In addition to its shade tolerance, St. Augustine grass is also known for its ability to recover quickly from damage. Whether it’s from foot traffic, pet waste, or lawn equipment, St. Augustine grass can bounce back and continue to thrive with proper care.

Key characteristics of this warm-season turfgrass include:

Bluish-green leaf color: Augustine grass has a distinct bluish-green hue that easily stands out in a lawn.
Coarse texture: The grass possesses a coarse texture, giving it a thicker feel than other grass species.
Low creeping habit: The grass spreads by stolons, allowing it to form dense mats and making it an excellent choice for a lush lawn.
Drought tolerance: While St. Augustine grass does require water to stay green in periods of drought, it doesn’t need more water than other grass species to remain green.

From my experience and research, I can confidently say that St. Augustine grass is an excellent choice for homeowners in regions with warm and humid climates.

The grass brings a unique, lush appearance to lawns and is adaptable to various weather conditions, ensuring a beautiful and thriving landscape.

Ideal Climate and Soil Conditions

St. Augustine grass prefers well-draining, moderately fertile soils. It can tolerate a wide range of pH levels, from acidic to alkaline, but prefers a slightly acidic soil pH between 6.0 and 6.5. It also prefers high levels of moisture, so make sure to water your St. Augustine grass regularly, especially during hot, dry weather conditions.

While St. Augustine grass can tolerate a variety of soil types, it does best in soils that are rich in organic matter. Adding compost or other organic amendments to your soil before planting can help improve soil structure and fertility, providing a better environment for your St. Augustine grass to grow and thrive.

When it comes to climate, St. Augustine grass is well-suited to the warm, humid conditions found in the southern United States. However, it can also be grown in cooler regions, as long as it is planted in a sheltered location and given proper care.

Photo Credit: Shutterstock.

St. Augustine Grass Care

Light

St. Augustine grass thrives in full sun, but it can also tolerate partial shade. If your lawn is in an area with partial shade, it may not grow as thick and lush as it would in full sun. Ideally, the grass should receive 6-8 hours of sunlight per day to grow to its full potential. If you have trees or other structures that cause shade, you may want to consider trimming them back or finding a different spot to grow your St. Augustine lawn.

Soil

St. Augustine grass prefers well-draining soil that is rich in organic matter. You can test your soil with a soil pH tester to ensure it is within the ideal range (between 6 and 7). If your soil pH is too low or too high, you can adjust it with lime or sulfur respectively. Additionally, it is important to ensure that your soil is not compacted. Soil compaction can lead to poor drainage, which can cause root rot and other issues. You can aerate your lawn to prevent soil compaction.

Water

St. Augustine grass requires regular watering, especially in hot and dry conditions. The grass should be watered deeply, but infrequently, to encourage deep root growth. The best time to water your lawn is early in the morning or late in the evening when the temperature is cooler.

Avoid watering during the middle of the day when the sun is most intense, as this can lead to water evaporation. Plus, it is important to ensure that your lawn is not overwatered. Overwatering can lead to soil compaction and other issues.

Generally, I water my lawn with about 1 inch of water per week, either through rainfall or supplemental irrigation. To conserve water and prevent evaporation, I irrigate my lawn in the early morning or late evening hours.

Temperature and Humidity

St. Augustine grass is sensitive to extreme cold and hot temperatures. It can withstand hot and humid conditions but doesn’t fare well in cool or freezing weather. Therefore, it is important to choose a time of the year when the temperature is above 70°F (21°C) to plant your St. Augustine grass. Additionally, it is important to keep humidity levels under control to prevent the development of fungal diseases on your grass. If you live in an area with high humidity, you may want to consider using a dehumidifier in your home to keep humidity levels in check.

Fertilizer

St. Augustine grass requires regular fertilization to thrive. I recommend applying a balanced fertilizer (like 16-4-8) two to four times a year, depending on the time of year and the condition of your lawn.

Nitrogen is particularly crucial for the growth of St. Augustine grass, so always look for a fertilizer with higher nitrogen content. Plus, it is important to ensure that you are not over-fertilizing your lawn. Over-fertilization can lead to excessive growth, which can attract pests or make your lawn more prone to diseases.

Personally, I apply slow-release nitrogen fertilizers following the recommended rates for my lawn size and grass type. A typical fertilization application schedule includes:

Spring: Apply a 16-4-8 fertilizer at a rate of 1 pound of nitrogen per 1,000 square feet of lawn area.
Summer: Apply a 15-0-15 fertilizer at 0.5 pounds of nitrogen per 1,000 square feet.
Fall: Repeat the summer application, but using a 15-0-15 fertilizer with a 2:1 potassium-to-nitrogen ratio.

Mowing and Thatching

St. Augustine grass requires periodic mowing to stay healthy and look its best. The recommended height for mowing St. Augustine grass is 3-4 inches, but make sure to adjust your mower blades accordingly to prevent scalping.

Never remove more than one-third of the grass height during one mowing. Cutting too much can damage the grass and leave it open to pests or diseases. Plus, it’s important to make sure that your mower blades are sharp. Dull blades can tear the grass, leaving it open to disease and pests.

Thatching occurs when dead grass and organic debris build up on the soil surface, blocking water and nutrients from reaching the grass roots. To prevent this, I dethatch my St. Augustine grass lawn annually using a rake or a specialized dethatching machine.

It’s also important to note that mowing too high will lead to a thatch problem and disease issues as the lower grass canopy will tend to stay wet.

Photo Credit: Shutterstock.

St. Augustine Grass Popular Varieties and Cultivars

Floratam

Floratam St. Augustine grass is a popular variety known for its dark green color and adaptability to various soil pH levels, ranging from 5.0 to 8.5. It thrives in USDA hardiness zones 7 to 12 and grows best at a mowing height of 3 to 4 inches.

Floratam is often compared to other grass types such as Bermudagrass and Buffalo grass regarding its overall performance, but it maintains a unique look and feel that sets it apart.

Seville

Seville St. Augustine grass is another variety that stands out due to its fine texture and low-growing nature. This cultivar is often praised for its shade and drought tolerance, making it a suitable choice for yards with tree cover.

Seville has a beautiful dark green color and a slightly lower height than Floratam, providing a more compact appearance in your lawn.

Floratine

Floratine St. Augustine grass is known for its resistance to pests and diseases, such as chinch bugs and fungus problems.

This cultivar is a good option for those who may struggle with maintaining healthy turf due to its low water and fertility requirements.

Floratine offers a dark green color and a medium texture, making it a great option between the coarser Floratam and the finer Seville varieties.

Charleston

Charleston St. Augustine grass is a cultivar specifically bred for its cold resistance. It can be more tolerant to colder climates compared to other St. Augustine grass varieties.

Charleston shares the same beautiful dark green hue as other members of the St. Augustine family and has similar requirements for soil pH, fertility levels, and mowing height.

Its adaptability to cooler weather has made it a popular choice in regions that experience fluctuating temperatures.

Photo Credit: Shutterstock.

How to Plant St. Augustine Grass

Now that you understand the characteristics and preferred growing conditions of St. Augustine grass, it’s time to plant your lawn. Here’s our step-by-step guide:

Choosing the Right Time to Plant

St. Augustine grass is best planted during the warm, rainy season, from spring through summer in most areas. Avoid planting during the winter months when frost is present. The soil temperature should be above 55 degrees Fahrenheit before planting.

It is important to choose the right time to plant St. Augustine grass because it is a warm-season grass that thrives in temperatures between 80-90 degrees Fahrenheit. Planting during the cooler months can result in poor growth and development of the grass.

Preparing the Soil

Before planting your St. Augustine grass, prepare the soil. Remove any weeds and debris, and till or aerate the soil as needed. It’s a good idea to add organic matter, such as compost or peat moss, to help improve soil fertility and drainage.

Preparing the soil is crucial for the success of your St. Augustine grass. The grass requires well-draining soil that is rich in nutrients. Adding organic matter to the soil can help improve its structure, allowing for better water and nutrient retention.

Laying Sod or Planting Plugs

When planting St. Augustine grass, you have two main options: laying sod or planting plugs.

If you choose to lay sod, make sure the pieces are snugly laid together and water immediately after planting. If you choose to plant plugs, space them about 12-18 inches apart, and water regularly until they fill in.

Laying sod is a quick and easy way to establish a St. Augustine grass lawn. The sod is typically grown on a farm and then harvested and delivered to your home. Planting plugs, on the other hand, takes longer to establish but can be more cost-effective.

Regardless of which method you choose, it’s important to keep the soil moist during the establishment period. This can take several weeks to several months, depending on the method you choose.

Stolons

Stolons, or above-ground runners, are another method for propagating St. Augustine grass. This method involves planting stolons directly into the ground, similar to how plugs are planted, but with a different plant structure.

Before planting stolons, I recommend preparing the soil in the same manner as for sod or plugs. Then, evenly space the stolons across the area and cover them with a thin layer of soil. Water the area regularly to ensure that the stolons establish and begin to spread, creating a new lawn.

Photo Credit: Shutterstock.

Common Pests and Plant Diseases for St. Augustine Grass

Chinch bugs, billbugs, and grubs are the most common pests that affect St. Augustine grass. These insects feed on the roots and stems of the grass, causing brown patches, thinning grass, and excessive thatch. If left untreated, these pests can quickly spread and cause significant damage to your lawn.

Southern chinch bug can be difficult to spot due to its small. The best place to look for them is along the edges of your lawn where it meets the road, patio, driveway, or sidewalk. This will help you get a side view of the turfgrass canopy to spot them.

There are several ways to treat pest infestations in St. Augustine grass. One effective method is to use insecticides specifically designed for the type of pest you are dealing with.

These products can be applied directly to the affected areas and will kill the insects on contact. It’s important to read and follow the instructions carefully to ensure safe and effective use of the product.

In addition to pests, St. Augustine grass can also be susceptible to fungal diseases such as brown patch and gray leaf spot. These diseases develop in warm, humid weather conditions and can quickly spread throughout your lawn if left untreated.

To prevent fungal diseases, it’s important to maintain proper lawn care practices. This includes regular watering and mowing, as well as ensuring your lawn has good air circulation. Avoid overwatering, as this can create a moist environment that is ideal for fungal growth.

If you suspect a fungal disease, it’s important to take action quickly to prevent further damage. One effective method of treatment is to use a fungicide specifically designed for the type of fungus you are dealing with.

Comparisons and Alternatives to St. Augustine Grass

Bermuda Grass

Bermuda grass, which is known for its fast growth and ability to withstand traffic, is another warm-season turfgrass that can be considered as an alternative to St. Augustine grass. It’s widely seen in sports fields and golf courses, thanks to its fast, aggressive growth.

In my experience, I have found that bermuda grass has a higher cold tolerance. Plus, it’s also more tolerant to drought and can handle full sun better than St. Augustine grass.

However, it may not be the best choice if you’re looking for a turfgrass that can handle shady areas since St. Augustine grass tends to have a better shade tolerance. It’s also better for coastal areas since it can tolerate salty conditions better than Bermuda grass making it a popular choice for coasts of Florida to Texas.

Key Differences:

Bermuda grass is more drought-tolerant than St. Augustine grass.
Augustine grass has better shade tolerance.
Bermuda grass can handle high-traffic areas better than St. Augustine grass.

Buffalo Grass

Buffalo grass is another alternative for warm-season turfgrass lovers. When comparing it with St. Augustine grass, I have noticed that buffalo grass is generally lower maintenance and more drought-tolerant.

In addition, its fine texture and blue-green color can give your lawn a unique appearance. However, it lacks the density and lushness that St. Augustine grass offers, which means it may not be suitable for high-traffic areas or if you’re aiming for a lusher look.

Key Differences:

Buffalo grass has lower maintenance requirements than St. Augustine grass.
Augustine grass offers a denser and lusher appearance.
Buffalo grass is not ideal for high-traffic areas.

Other Warm-Season Turfgrasses

Besides Bermuda grass and Buffalo grass, I’ve come across other warm-season turfgrasses like Zoysia grass and Centipede grass that can be alternatives to St. Augustine grass.

Zoysia grass is known for its attractive appearance, drought tolerance, and ability to grow in a wide range of soil types. It is also more cold-tolerant than many other warm-season grasses. However, it has a slower growth rate compared to St. Augustine grass.

Centipede grass, on the other hand, is a low-maintenance, low-growing grass that performs well in sandy, acidic soils. It shares some similarities with St. Augustine grass in terms of shade tolerance, but it tends to be less dense and can handle wear and tear better.

Zoysia grass: