St. Augustine grass and Bahia grass are two warm-season turf grasses that both grow well in warm and sunny conditions. However, despite this and a few other similarities, there are significant differences between these two grass varieties.
The main difference between Bahia grass and St. Augustine grass is the color and shape of leaves. Bahiagrass has crow-shaped, light green leaves while St. Augustine grass has broad coarse, blue-green leaves. Of the two, Bahia is more drought-tolerant and requires less water than St. Augustine grass.
Bahia grass Identification
Bahia grass, also referred to as Highway grass, is an evergreen, warm-season turf grass species that’s native to Central America. Its most unique identifiers are the V-shaped seed heads. The two V-shaped spikes on every Bahia grass plant form at the tip of the flower stalk and are basically stems with clustered flowers on them.
Note: The clustered flowers on Bahia grass are usually small in size and are black or dark-brown in color.
The leaf blades of this grass species are light green in shade and are coarse-textured. Bahia grass leaves typically fold to form open canopies.
Bahia grass grows aggressively through lateral-growing, underground stems known as rhizomes, which is why it’s listed as an invasive grass species. The rhizomes are usually located just below the ground surface and appear as clumps. Bahia grass rhizomes are typically red or pink in color.
Bahia grass produces large quantities of seeds, with the number of seeds produced slightly varying depending on the variety. There are four common Bahia grass cultivars; namely Pensacola, Argentine, Common, and Paraguay Bahia grass. Argentine Bahia is noticeably darker than other Bahia grass cultivars and also forms thicker sod.
St. Augustine grass Identification
St. Augustine grass (Stenotaphrum secundatum) is a perennial grass species that’s popularly grown on lawns due to its dense growth pattern. This turfgrass variety only spreads via above-ground stems (runners) known as stolons (it lacks underground rhizomes).
Note: St. Augustine stolons are noticeably narrow and branch out at several points.
St. Augustine grass leaf blades are thick (3-5 mm wide), of medium height (15-30 mm long), have rounded edges, and feel coarse to the touch. They’re also flat, with a dark-green shade. St. Augustine leaf blades are smooth and hairless, with the collar section being the only exception.
Another unique identifier of St. Augustine grass is the heavily-compressed stem/sheath section. They’re so compact to the point that it takes some elbow grease to pull them apart. Meanwhile, the St. Augustine grass flower is a single raceme with spikelets.
There are several St. Augustine grass cultivars, each of which varies slightly from the next. Some of its most common varieties include Palmetto, Floratam, Bitter-Blue, Sapphire, and Floralawn St. Augustine.
Bahia grass vs. St. Augustine – Differences
Some notable differences between St. Augustine grass and Bahia grass include the leaves, flowers, seeding rate, growth rate, and growth pattern. They also differ in terms of their aesthetic appeal, maintenance requirements, shade tolerance, wear tolerance, and pest/disease resistance.
You can also differentiate between Bahia grass and St. Augustine grass by the type of flowers that they develop. In Bahia, two spikes branch out from the stalk, forming a V-shape as flowers line up on the spikes. By contrast, St. Augustine grass flower is a single spike/raceme (3”-5” long).
While Bahia grass produces massive amounts of seed, St. Augustine has a much slower seeding rate. Grass nurseries commonly offer both Bahia grass seed and sod for homeowners looking to establish a Bahia lawn. By comparison, St. Augustine doesn’t produce enough viable seed, and that’s why nurseries typically offer St. Augustine sod only for lawn establishment.
Since Bahia produces seeds at a faster rate than St. Augustine turf grass, it grows and spreads faster to form a fully-established lawn. St. Augustine grass is a slow grower and it takes patience and proper care and maintenance to establish a lush, fully-covered lawn from this type of grass.
Due to its thick grass blades, St. Augustine grass exhibits dense growth with a fuller appearance, making for beautiful lawns. Unsightly weeds are also harder to spot in this type of lawn due to the dense growth pattern.
On the other hand, Bahia grass has thinner blades, making invasive weeds more visible in this type of lawn. Bahia grass also has tall V-shaped blooms that make this turfgrass species look like ugly weeds if not trimmed.
Bahia grass is more resistant to grass diseases compared to St. Augustine grass. Despite its better pest and disease tolerance, though, Bahia grass can still suffer leaf yellowing due to iron deficiency in the soil. Meanwhile, St. Augustine turfgrass is vulnerable to a wide range of grass plant diseases, most commonly Nigrospora stolon rot, brown patch disease, and take-all root rot.
St. Augustine grass is generally harder to maintain compared to Bahia grass. The latter variety is more drought-tolerant due to its deeper root system. Thus, it doesn’t need to be watered as frequently or as much as St. Augustine grass.
The downside to this, though, is that Bahia doesn’t react well to being overwatered or overfed. Your Bahia turf grass will quickly die if you waterlog or over-fertilize it. By contrast, St. Augustine grass holds up better to frequent hydration. This turfgrass species also needs high amounts of nutrients to thrive and is thus unlikely to suffer from over-fertilization.
St. Augustine grass is more shade tolerant than Bahia grass. The former grass species will still thrive in partially shaded lawns. Bahia grass, on the other hand, doesn’t thrive even in partial shade and will likely suffer stunted growth in such conditions.
Bahia grass has better wear resistance in comparison to St. Augustine grass. High traffic will quickly ruin St. Augustine turfgrass. By contrast, Bahia grass can withstand heavy usage once it’s well-established.
Note: Despite Bahia having greater wear tolerance, young Bahia grass is also vulnerable to wear and tear due to its shallow root system. Also, improper mowing and lawn maintenance makes even established Bahia lawns less durable.
While both of these turfgrass species are warm-season varieties that thrive in warm and sunny climates, Bahia grass is more drought-tolerant than St. Augustine grass. You need to frequently water your St. Augustine grass if you want a lush green lawn, while Bahia suffers when irrigated too often.
St. Augustine and Bahia grass also vary in terms of growth patterns. While St. Augustine spreads by way of above-ground stolons, Bahia grass spreads via underground rhizomes.
Which Grass to Choose
Your individual needs should lead you in determining the better choice for you when choosing between Bahia grass and St. Augustine grass. Some of the factors that should guide you in your decision-making include your budget, whether your yard is erosion-prone, and whether your lawn is shaded or not.
Choose St. Augustine grass if:
- You have tall trees/ shrubs on your lawn– St. Augustine grass will still thrive in a partially shaded lawn. Bahia grass, on the other hand, doesn’t do well in shaded conditions and requires full sunlight exposure to thrive. Thus, if you have trees and shrubs that shade sections of your lawn, St. Augustine is the way to go.
- You want a denser, beautiful lawn– St. Augustine grass forms denser turf than Bahia grass, and is thus considered the more attractive and desirable option between the two. Additionally, weeds are easily visible on Bahia grass blades due to the thinner grass blades, while St. Augustine crowds out weeds due to its thick growth nature.
- You want to grow grass for pasture– due to its dense growth, St. Augustine yields high quantities of grass, making it great for use as pasture. The fact that it’s also resistant to high temperature and humidity conditions also means that you’ll still harvest abundantly even if you live in an arid or semi-arid region.
Choose Bahia grass if:
- You want a fast-growing lawn– Bahia will quickly spread to fully cover up all the bare patches on your lawn. This grass variety yields large amounts of seed and also spreads aggressively via its rhizomes. Comparatively, St. Augustine grass grows slowly and typically takes several months to form a dense turf.
- You’re looking to prevent soil erosion- say for instance, that your yard is sloppy (not flat) and is prone to soil erosion, you can control the problem by growing Bahia turf grass. This grass variety has deep-growing roots, making it great for stabilizing slopes and preventing rainwater from washing off soil from your erosion-prone yard.
- You’re working on a budget– it costs more to grow a St. Augustine lawn compared to a Bahia lawn. This is due to the fact that St. Augustine is typically grown via vegetative propagation (sod) which is comparatively costlier than planting Bahia grass seeds (seeding is the most common way of establishing Bahia lawns).
Note: It costs $300-800 dollars to buy 1000 square feet worth of sod. By contrast, 10-lbs of Argentine Bahia (which is enough to cover up to 1000 square feet) costs $160 dollars or thereabouts.
Can you mix Bahia grass with St Augustine?
You can successfully overseed your St. Augustine lawn with Bahia grass seed, but you’ll have to ensure the conditions are right. For instance, if the lawn is shaded, your overseeding project is likely to fail. Bahiagrass doesn’t stand up to shaded conditions as well as St. Augustine.
What’s more, St. Augustine grass widely differs from Bahia in terms of physical appearance. Also, St. Augustine grass typically chokes out Bahia, making it harder to successfully grow these two turf grass varieties on the same lawn.