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St. Augustine and Zoysia are popular grass options in the southern United States due to their aggressive growth and relative drought tolerance. While both kinds of grass will survive in most southern lawns, they are each suited to different climates and soil conditions.
So, which grass should you choose for your new lawn?
- St. Augustine is a better choice for establishing a new lawn in well-drained, fertile soil with consistent moisture.
- Zoysia is preferred if you are establishing a new lawn in poor soil that can become compacted.
Both grasses can tolerate salt, drought, and some shade, although zoysia is easier to maintain.
There are many factors that can determine which turf you choose, but first, Let’s dive into the basics of each grass.
St. Augustine vs. Zoysia: The Basics
Both St. Augustine and zoysia are warm-season grasses with roughly the same growing regions. However, they each thrive in different climates, and they have different appearances, which may influence your turf choice.
|Pests||Grubs and Sod Worms||Chinch Bugs|
|Diseases||Brown Patch and Grey Leaf Spot||Brown Spot, Rust, and Leaf Spot|
St. Augustine grows in subtropical regions of the United States, and it is most common along the coasts due to its high salt tolerance. St. Augustine will require supplemental irrigation in dry climates. Although this turf stays green longer than zoysia, once it turns brown, it’s dying, not going dormant.
St. Augustine is a dense, bluish-green turf that should be mowed 2”-4” tall. Once established, St. Augustine chokes out most weeds, making sprays unnecessary in most lawns.
However, St. Augustine is susceptible to a few pests and diseases. Spray for grubs and sod worms each spring to prevent infestations, and apply a fungicide to prevent brown patch and grey leaf spot (source).
St. Augustine tolerates extremely high summer temperatures as long as it has enough moisture. If you are establishing a new lawn, you can find some varieties that are more cold-tolerant, and others that require less-frequent mowing.
Zoysia thrives in the southeastern United States, but it can tolerate regions as far north as Nebraska. Zoysia also tolerates salty soils, but this is more consistent with dry climates that have salt buildup due to lack of rainfall rather than coastal regions.
Zoysia is a low-growing grass with a dense root system and tolerates drought better than St Augustine. After a week without moisture, zoysia will go dormant until the next rainfall, and then quickly green up again.
During a drought, zoysia may appear to be less resilient than St. Augustine, but zoysia always recovers from drought with irrigation or rainfall, while St. Augustine may not recover once it has turned brown.
Chinch bugs are the most common pest that affects zoysia. This insect attacks during hot, dry periods of the summer and can look like drought damage.
However, zoysia has a high drought-tolerance, so if you notice brown patches that don’t recover after irrigation, treat for chinch bugs before they can spread to the rest of your turf.
Zoysia is susceptible to brown spot, rust, and leaf spot. All of these diseases can cause grey or brown spots in the lawn or on individual leaves. Proper maintenance will help prevent most diseases, but you may need to spray if large areas are affected.
Learn more about Zoysia grass from our comprehensive guide on establishing and maintaining a healthy Zoysia lawn.
Besides climate, soil is the most important factor for turf choice. St. Augustine and Zoysia have similar growing zones, so which grass you choose will come down to your soil classification and how much effort you want to put into improving the soil in your yard.
|Soil Type||Best Grass Choice|
|Silt||St. Augustine or Zoysia|
|Sand||St. Augustine or Zoysia|
You can use a simple test to determine your soil texture.
Wet a handful of soil so that it is moist but not dripping. Squeeze the soil firmly.
- If it holds its shape without crumbling, you have clay.
- If it holds its shape but crumbles easily, you have silt.
- If it doesn’t hold its shape, you have sand.
Darker soils have a high organic matter content, which means it should hold onto nutrients well and retain moisture without becoming waterlogged. The only way to determine your soil’s fertility and pH is with a soil test.
Best Option: Zoysia
Zoysia handles clay soil much better than St. Augustine. Clay soils tend to become compacted, which leaves very little pore space for drainage. Zoysia is one of the recommended species of warm-season grass for clay soils.
Related Reading: Will Zoysia Grow In Clay Soil? Here Are The Facts
Suitable For Either Grass Type
Silt tends to act like clay under most conditions. Silty soils can become compacted under high traffic, but they are easier to amend with compost, and they usually have better drainage than clay. Zoysia will do well in most silty soils, and St. Augustine will do well as long as the soil drains well and has low foot traffic.
Suitable For Either Grass Type
Zoysia has a deep, dense root system that grows well in sandy conditions. Sandy soils drain easily, which can contribute to drought conditions in dry climates.
Fertility, Organic Matter, and pH
|Fertilization||Higher nitrogen requirements||Lower fertilization requirements|
|Drainage||Needs good drainage||More tolerant of poor drainage|
St. Augustine has higher nitrogen requirements than zoysia, so it needs a fertile soil or consistent fertilizer applications. St. Augustine also requires good drainage, which means a silty or sandy soil and higher amounts of organic matter.
This grass can tolerate a pH of 5.0-8.5 (source), giving it a larger range than zoysia.
Zoysia does not require as much fertilization as St. Augustine, which makes it the better choice for poor soils.
It also tolerates poor drainage better though this should be taken with a grain of salt. Extremely poor drainage in compacted clay will prevent almost any grass from thriving.
Zoysia can only tolerate a pH of 5.8-7.0, which makes it less versatile than St. Augustine.
Growth Habits of Zoysia and St. Augustine Grasses
Both St. Augustine and zoysia are warm-season grasses, which means they have a similar growth habit.
Warm-season grasses are generally creeping grasses, which means they send out runners to put down roots and establish new leaves. This is what makes them excellent for sports fields because they recover quickly.
Both grasses tolerate some shade, but St. Augustine is more shade tolerant than zoysia.
|Spreads through runners||Effective at choking out weeds||Damaged easily by aggressive dethatching|
|Higher shade tolerance||Fills in quickly|
St. Augustine has above-ground runners, known as stolons, which creep along the soil and put down roots. Stolons allow the grass to fill in quickly as long as there is adequate moisture.
If the lawn is mowed too short, or if you use a power rake to dethatch, you will damage the stolons and your lawn may not recover.
If St. Augustine is maintained well, it can choke out most weeds without help from herbicides. St. Augustine can thrive in moderate shade, so it is able to choke out weeds and other grasses in shady yards better than zoysia.
|Spreads both above ground and below||High drought tolerance||Slow to spread and fill in|
|Recovers well from low-height mowing and dethatching||Does not choke out weeds as soon as St. Augustine grass|
|Lower shade tolerance|
Zoysia spreads with stolons, like St. Augustine, but it also spreads using below-ground runners called rhizomes.
The rhizomes are protected from the sun and mower blades, which makes zoysia more drought-resistant and able to recover much easier from short mowing heights or dethatching.
Zoysia can choke out weeds in sunny areas of the lawn once it is established. However, new zoysia lawns may take 6-8 weeks to begin active growth, so you may need to spray a broadleaf weed control during the first year.
St. Augustine vs. Zoysia: Care Schedule
Both St. Augustine and zoysia are warm-season, creeping grasses with good drought tolerance. Therefore, the care schedules are very similar, with St Augustine being slightly more labor-intensive than zoysia.
Improving the soil will cut down maintenance requirements of both kinds of grass, so topdressing after aeration each year will gradually cut the time and money invested in your lawn. (See Does Lawn Aeration Really Work? Side By Side Comparison)
- Tolerates mowing 2″-4″
- Avoid aggressive dethatching or aerating
- Can be mowed as low as 3/4″
- Better toleration of aeration and dethatching
St. Augustine Annual Maintenance
St. Augustine is a low-maintenance grass under the right conditions. However, it has a lower tolerance of poor soils and poor drainage, which may disqualify this turf as an option in your climate.
St. Augustine is susceptible to drought year-round, so it’s important to monitor for drought stress and irrigate as needed. If your lawn turns a bluish color, or if footprints remain when you walk across it in the evening, irrigate ¾”-1” the following morning (source).
If St. Augustine begins to turn brown, it is dying, not going dormant. For more information, read Is St. Augustine Grass Drought Tolerant?
St. Augustine should be mowed May-October 2”-4” with a sharp blade. St. Augustine does not handle dethatching with a power rake, so it is important to mow frequently to prevent long grass clippings or clumps of grass.
If thatch is a consistent problem, try bagging your lawn clippings every other time you mow, which will help keep thatch at a manageable thickness. Mow every 5-14 days to maintain the proper height.
Recommended Reading: St. Augustine Lawn Care Fertilizer Schedule (Free Printable)
St. Augustine does not handle power-raking, but you can use a hand rake each spring to remove an unhealthy thatch layer.
Annual aeration can help manage thatch, but because St. Augustine does not have rhizomes, the aerator must be set to remove fewer cores so that it can fill in before summer. See Can You Dethatch St. Augustine Grass? Let’s Settle This!
Zoysia Annual Maintenance
Zoysia tolerates a wider range of climates and soils than St. Augustine. It is also more tolerant of dethatching.
Zoysia is drought-tolerant and will go dormant within 7 days of hot, dry conditions. If you want to prevent dormancy, irrigate as needed April-October at 1”/week (source).
Mowing height depends on the variety, but most varieties should be mowed ¾”-2.5” with a sharp blade from April-October. Mow as frequently as needed to prevent breaking the 1/3rd rule, which is generally every 10-14 days.
Zoysia may need dethatching every few years, but this can be reduced by practicing annual core aeration. Aerate from April-September each year, and dethatch if there is more than ½” of dead grass clippings.
When To Choose St. Augustine
St. Augustine is a good turf grass for hot, humid, coastal climates with sandy soil. It will tolerate a wider range of temperatures than zoysia, but it must have good drainage and consistent irrigation in order to thrive.
St. Augustine needs more frequent mowing, irrigation, and fertilization than zoysia. It does not hold up to foot traffic as well as zoysia, and it does not fill in as fast after aeration or damage.
Plant St. Augustine if your lawn drains well, receives consistent rainfall or irrigation, and has shaded areas.
How To Plant St. Augustine
The cheapest, but most labor-intensive method of establishing a St. Augustine lawn is to use sprigs.
Sprigs are sections of stolons cut from sod that you spread over bare soil and press into the lawn with a heavy roller. This can be a difficult way to establish a lawn unless you can keep it moist for 4-6 weeks while the stolons establish a root system.
An easier method is to use plugs, which is small sections of cut sod spaced apart across the lawn. Plugs have an intact root system, which makes it easier to keep alive after planting and helps the lawn fill in faster than sprigs. Space plugs 6”-12” apart.
The most expensive way to establish St. Augustine is with sod. This will result in an instant, weed-free lawn. However, St. Augustine is one of the more expensive sod choices at $.30-$.70/sq’.
Plant St. Augustine three months before the first frost and keep it moist. Most soils will need a starter fertilizer to help the turf establish roots quickly, and you may need to fertilize every 6 weeks until the first frost to help the turf prepare for cooler weather.
When you prepare your lawn for St. Augustine, mix in 3”-6” of high-quality compost to help with drainage and improve fertility.
When To Choose Zoysia
Zoysia is a more versatile turf grass than St. Augustine, and it is fairly low-maintenance in the right climate. It is slightly less salt tolerant than St. Augustine, which makes it a better choice in drier climates that may have salt buildup and less annual rainfall.
Zoysia doesn’t need mowed as often as St. Augustine, and it is tolerant of a wide range of poor soils. It handles dethatching and aeration well, so if you topdress each year with compost, you may be able to skip fertilizing and irrigation.
Zoysia does not handle shade as well as St. Augustine, so in a humid climate with shady areas, St. Augustine would be a better choice. Under most other conditions, however, zoysia is the better option if you don’t mind your lawn going dormant during dry seasons.
Plant zoysia if your lawn has high-traffic areas, gets inconsistent moisture, and has poor soil.
How To Plant Zoysia
Zoysia is a resilient grass, but it can take a while for it to fill in and establish a thick lawn. One major benefit to planting zoysia rather than St. Augustine is that zoysia has viable seed options, which is by far the cheapest way to establish a new lawn.
You can also establish zoysia from sprigs, plugs, or sod. Zoysia may have difficulty establishing a root system from sprigs, so the more common planting method is to use plugs. Purchase Zoysia plugs from a reputable grower where they are guaranteed to grow or replaced free (link to Zoysia Farms).
Zoysia sod is more expensive than St. Augustine, and can cost anywhere from $.50-$.85/sq’ foot. As with most sod options, there are some varieties that are more shade or pest tolerant that are only available in sod form, so in some climates it may be worth it to plant sod because you won’t have to wait as long for good coverage.
You can plant zoysia any time from mid spring to 8 weeks before the first frost. Keep zoysia consistently moist until you begin to see active growth from sprigs, plugs, or sod.
Seeds may take up to 3 weeks to germinate, and you must keep the soil moist during that time. Therefore, it may be easier to plant seeds in the spring when there is more rainfall and the temperatures are lower.
While zoysia is a good choice for low-maintenance lawns, there are some climates where St. Augustine is the better option. The first step in establishing a new lawn is to do a soil test (link to Amazon) so you can properly prepare the soil before you plant.
Healthy maintenance practices are the key to a lawn’s success, so make sure that no matter which turf you choose, you follow a consistent maintenance schedule that includes aeration, topdressing, proper irrigation schedules and mowing heights.
Recommended Reading: Best Fertilizer For Clay Soil Lawn: Why Ingredients Matter