Bermuda Grass vs. St. Augustine (Turf Comparison)

When you live in a hot climate, it may seem like you’ve only got two main grass types to choose from, especially if you want a low-maintenance lawn that’s going to survive when the water supply drops. So which grass, St. Augustine or Bermuda, is going to be best for your situation? Below is an in-depth comparison that should help you make the right choice.

Comparing St. Augustine vs. Bermuda Grass

The main points to pay attention to when you’re comparing Bermuda vs St. Augustine are ideal height when mown, cost to install, maintenance needed, sun and general topography, and natural soil type. For two grass types that look so similar, this may seem like a long list of differences and it is. Each of these points could make the difference between the perfect lawn for your situation and one that’s a bit on the patchy side and won’t seem to stay green when you expect it to.

Appearance of St. Augustine and Bermudagrass

At first glance, it can be difficult to tell a St. Augustine lawn from a Bermudagrass lawn. Both varieties are low-growing. They both have a deep green color when healthy and the blades of grass are broad, coarse, and thin. St. Augustine, however, has blades that are a little wider than those of Bermuda. Both types also produce stolons or “above-ground roots” that thatch over each other and help create a stronger lawn. Bermudagrass has also been known to produce rhizomes though it does so with less frequency than other grass types.

Best Uses for St. Augustine vs Best Uses for Bermuda

This is the section for a quick answer to which grass type, Bermuda or St. Augustine, is going to be better for your situation. For example, the best use for Bermudagrass is a very hot, sunny lawn that gets an average amount of traffic. The soil should be rich and well-drained and the lot will, ideally, be flat or have a gentle curve.

For a St. Augustine lawn, the best use would be a low-traffic lawn with poor, sandy soil and a neutral pH. Full sun or dappled shade is just fine. A yard in zone 8b through 10b would be ideal. Flat terrain is also better than sloped.

Soil Types and pH Needs of St. Augustine vs Needs of Bermudagrass

Both Bermuda and St. Augustine grass need a neutral pH and well-drained soil. Drainage is key because both of these types of grass are highly susceptible to water-based diseases, including root rot. St. Augustine also prefers sandy soil and thrives in nutrient-poor situations. Bermudagrass will need a bit more fertilizer over its life and does better in loamy soil, though it can tolerate some sand.

Water Needs for St. Augustine Lawns vs Water Needs for Bermuda Lawns

When it comes to water needs, Bermuda grass has a higher water uptake rate than St. Augustine however, Bermuda grass is also much more likely to hold onto this water and stay green during a drought. St. Augustine only needs an inch of water a week, but it will take up much more if given the chance. Its broad grass blades will then dissipate this surplus moisture. While this can help cool the St. Augustine grass itself and help keep it from scorching in hot weather, it also means that any plant near St. Augustine will have to fight that much harder to get the water it needs.

Bermuda grass only needs an inch to 1.5 inches of water each week. It’s more polite than St. Augustine and can stay greener for several weeks after the color of St. Augustine would fade during a drought. Further, while the ideal mowing height for Bermudagrass is lower on average, it can be allowed to grow out a bit during low water conditions to help it conserve even more moisture.

Sun, Shade, and Temperature Requirements for St. Augustine vs Bermuda

Bermudagrass needs full sun. It cannot tolerate shade of any kind and will thin in even dappled shade. In deep shade, Bermuda will die back or refuse to grow. Bermuda is, however, tolerant of a larger temperature range than St. Augustine. Bermudagrass will go dormant at 32F and can tolerate a brief, light frost or freeze before serious damage is done. It will stop growing at and below 55F as well as at and above 85F without frequent watering.

St. Augustinegrass prefers full sun but can handle dappled and part shade very well. If you have any deep shade areas in your yard you may want to mix in a more shade-tolerant grass for these spots. St. Augustine needs a hotter climate than Bermuda to thrive. Zones 8b and up are best. St. Augustine will go dormant at and below 55F. This grass type cannot tolerate freezing or even temperatures close to freezing for any length of time. Any sort of frost will cause damage. St. Augustine rarely goes completely dormant, even at high temperatures, which makes it more susceptible to drought than Bermudagrass.

Durability of Bermuda Grass vs St. Augustine Lawns

Bermudagrass and St. Augustine are both lower-durability than grasses that do not grow from stolons. As stolon-based grass types, both Bermuda and St. Augustine hold up well, but Bermudagrass will do a bit better given the extra structure its rhizomes provide. St. Augustine grass should be used on a flat lawn whereas Bermudagrass can handle a gentle slope. Neither will do well on hills if any traffic is expected after wet weather.

Beyond terrain, Bermuda and St. Augustine both handle being dug up and cut equally poorly. Often, clumps of Bermuda grass will refuse to root after being pulled up and nearby clumps will need to fill in the area. St Augustine should root but will do so slowly, just as it would if it needed to fill in a bare spot.

Common Pests and Diseases for St. Augustine or Bermudagrass

Bermuda grass is susceptible to the usual ants, webworms, thrips, and digging animals. Water damage or standing water is a real concern as it can lead to moss, algae, and mildew growth very quickly. If left alone and drainage is not improved, these conditions can lead to root rot.

St. Augustinegrass is similar in that it is susceptible to these usual insects as well as nematodes and chinch bugs. Chinch bugs in particular can devastate a St. Augustine lawn in less than 2 weeks. Like Bermuda, St. Augustine is also prone to root rot. Brown patch and fungal diseases are also a concern. Further, St. Augustinegrass has an even lower tolerance for too much water than Bermuda and even long, heavy periods of rain can cause these conditions or diseases to set in.

Mowing Needs of St. Augustine vs Mowing Needs of Bermuda Grass

St. Augustine should be mown to a height of 2” to 2.5”. Allowing it to grow longer in hot weather isn’t as beneficial as it is to other types, due to the angle of growth. St. Augustine will grow fastest in early summer but is still a slow-growing grass type. Bermudagrass should be kept at a low 2”, on average. Allowing it to get a little long in hot weather can be beneficial and reduce the amount of moisture needed to keep the Bermuda lawn green.

Are There Better Strains of St. Augustine or Bermuda?

The varieties of Bermudagrass on the market can help you deal with a handful of different problems. Some types are a darker color, others require less water, and some will produce a thicker lawn. Whatever your needs are, contacting a local dealer is the best first step. Some varieties will be available online or at seed stores but others may be “region locked” due to distribution agreements.

St. Augustinegrass has far fewer strains available but there are two worth noting. First, ‘Captiva’ will help nearly eliminate the chinch bug problem St. Augustine tends to be plagued with. If you’re not worried about chinch bugs in your region, ‘Variegatum’ is also worth considering, especially if you have a shaded yard. This variety produces a lawn with blades of grass in dappled shades of green and white.

Cost of St. Augustine vs. Bermuda

Bermuda grass is easy to get and relatively cheap for any grass type. Common strains are available for as low as $8/lb at the time this article was written. More “premium” strains can be double that, but the advantages are often worth it.

St. Augustine is pricier as it often does not produce viable seeds. This means sod and plugs are the only way to get a strong, consistent St. Augustine lawn. For enough plugs to cover an average-sized lawn, you’ll be looking at around $800 to $1200, depending on where you live and what tools you already have.

Can You Mix Bermuda and St. Augustine Grass?

You can mix Bermudagrass with St. Augustine. First, you want St. Augustine as your primary grass. Install the plugs and then overseed with Bermudagrass. The Bermuda will help fill in your lawn quickly while the St. Augustine establishes itself. Over time, expect that the St. Augustine will overtake the Bermudagrass, especially in any shaded areas or in hotter climates.

The Best-Case Scenario for a St. Augustine vs Bermuda Grass Lawn

For a Bermudagrass lawn, the best-case scenario would be a flat yard with full sun and no freezing winter. Low traffic is also ideal. This isn’t the type of lawn you want if you plan to park on the lawn or if you have a lot of outdoor pets. If you’re still struggling to decide whether it’s the right choice, you may find this article I wrote on the pros and cons of Bermuda grass a useful read.

For a St. Augustine lawn, a residential lawn with good drainage, poor, sandy, hot soil, and a flat yard is ideal. Low traffic conditions are also recommended for this grass type.

To summarize the main points when comparing Bermuda grass vs St. Augustine, I’ve put together the table below.