Last Updated on July 3, 2020 by Kimberly Crawford
If there is another turf grass that is as common and as famous, it would be St. Augustine.
It is known as both a good turf grass and a forage/pasture grass native in coastal areas.
And although it is a seasoned warm climate grass, it could well tolerate shady areas. But of course, there is no perfect grass type and if you plan to doze in your bucks on it, you have to know everything about it first and here is what this post is about.
What is St. Augustine grass?
This grass goes by the botanical name Stenotaphrum secundatum. It is a robust and dense perennial grass that grows well in warmer climates but could also tolerate shade.
It thrives well in well-draining soils and can grow with minimal salt. It grows coarse textured blades that have distinct deep green to blue green colors thanks to its hardiness range of 8-10.
A lot of agronomists would say that it is the easiest grass to take care of and unlike Bermuda and the zoysia, it does not go dormant immediately during the winter.
As turf grass, it is very popular in the Caribbean, South America, Australia, Mexico and in the US, specifically in warmer, subtropical climates like Florida and Hawaii.
What does St. Augustine grass look like?
First off, unlike Bermuda, St. Augustine is not rhizomatic. As have been mentioned, St. Augustine grass is distinct for its deep green to blue green color. Its leaves have a coarse texture.
They are thick with rounded tops and more compact as it goes down to the stalks. It grows in stolons and roots via nodes. It is one of the most shade tolerant warm season grasses. It really grows dense that is why it is a popular choice both as turf grass and as pasture grass.
What are the benefits of St. Augustine grass?
There are various reasons why the St. Augustin grass is a popular choice. It comes with lots of grass benefits such as the following:
- Unlike other warm season grasses, the St. Augustine can thrive in colder regions and can grow in shady areas.
- It remains dark green in color during the colder seasons unlike other warm season grasses that will grow dormant immediately.
- It has high recuperative potential and can accommodate moderate to high foot traffic.
- It can thrive in various soil types even in coastal, high saline soils.
Beyond this, the benefits of St. Augustine grass go beyond more than just being turf grass.
For one, it is used in forage production because of its distinct nutritional quality for graze animals. Aside from this, its dense growth is known for suppressing weed growth in the garden, saving you of herbicides and of course, your soil’s natural nutrient content.
Most importantly, it is used as a living sod in many plantations in the US specifically for coffee, banana, macadamia, coconut and papaya cropping systems.
St. Augustine grass pictures
Given the aforementioned basic characteristics and benefits of the St. Augustine, it is but right to show what it looks like. Here are some pictures of St. Augustine.
Types of St. Augustine grass
Being a popular turf grass choice, the St. Augustine is developed continuously and at present has three species (Raleigh, Palmetto and Floratam) and eleven cultivars.
Although it does not produce its own seed and no seed is available in the market to be bought, the demand remains high because of its beneficial characteristics. As such, here are the most common St. Augustine grass types out there.
#1. Seville St. Augustine Grass
This St. Augustine grass really established its good reputation among residential landscapes. It is one of those dwarf cultivars but performs well for many reasons.
Aside from being able to tolerate drought, shade, salt, and all pH ranges from acidic to alkaline it also has high color retention even during the winter. It is generally low-maintenance after it establishes its roots.
#2. Raleigh St. Augustine Grass
This one is a cold hardy and was developed as a cultivar in Raleigh, North Caroline in the 1980, hence the name. It is tolerant to up to 10 degrees with paler green color, coarse texture and is disease resistant.
It loves heavy, clay soils with high organic matter and will thrive medium to low pH levels in the soil.
It is known for being drought, cold and shade tolerant but at the same time, it is also known to get yellow and have stunted growth on very high temperatures although it is considered to be the cultivar who needs constant, full sun exposure.
#3. Palmetto St. Augustine grass – Best Shade Grass
This St. Augustine grass is oftentimes compared to Raleigh but in many respects, it is fairly distinct on its own. For one, Palmetto is a native St. Augustine cultivar with finer texture and with more solid green color.
Like Seville and Delmar, it is also a dwarf type but unlike them, it will not develop too much thatch.
Compared to its cultivar cousins, the Palmetto is known for having more superior tolerance to shade, drought, cold/frost and salt. It could also tolerate a variety of soil types and pH levels making it a go-to choice for residential and commercial ground/lawn cover.
#4. Floratam St. Augustine grass
This is the third native species of the St. Augustine grass and is the most widely produced and commercially sold because it is the most low-maintenance, hence, also the most cost-efficient.
It grows vigorously and the most coarse-textured of them all. It was developed to be both drought and disease resistant (which includes brown bug, chinch bug, downy mildew, green leaf spot and the SAD virus). It is also considered as the most drought-tolerant variety of all St. Augustine grasses.
#5. Mercedes St. Augustine grass
It was a cultivar developed by the University of Florida in the 1980s and has a relatively similar look with the Raleigh. It grows roots through stolon and in a rhizomatic way.
It is drought and shade tolerant. It is also very much accommodating to moderate to high traffic. It also has high wear strength and has high recuperative potential.
It is also loved by residential and commercial owners because it retains its blue-green color even when the temperature gets relatively low. However, it is very susceptible to chinch bugs.
#6. Sapphire St. Augustine Grass
This one has the fastest lateral growth rate allowing it to have high recuperative potential which helps it revive blank spots and wear faster than others.
It is also known for having the best blue-green color of them all.
It thrives in subtropical climates and is highly drought-tolerant. However, you must know that it is not very susceptible to diseases especially brown fungus. This means that you have to re-sod your lawn annually, which means that you have to invest more.
#7. Bitter-Blue St. Augustine Grass
It is one of the earliest improved varieties of the St. Augustine.
It is denser, finer and has a more blue-green color. While it has good resistance to cold and drought, it is not as superior compared to Seville and Palmetto.
It is salt tolerant though and can accommodate moderate foot traffic.
A few downsides are associated with it though: it is not resistant to gray leaf spots and chinch bugs. So while it is a very good lawn cover, it would need high lawn care maintenance which includes pest control.
#8. Evergreen St. Augustine Grass
It is a semi-dwarf variety known for its plusher, dark-green color with narrower and shorter blade leaves.
It is listed in the top rank of the most shade-tolerant St. Augustine grasses but also thrives in full-sun.
It is also known for its good color retention and could turn to its green color faster than others after the winter cold and one of the few grass varieties that could retain its color through fall. It has fine leaves but it could not tolerate high foot traffic.
#9. Delmar St. Augustine Grass
It is distinct for its emerald green color and medium coarse texture. It is moderately drought tolerant and has fair shade tolerance.
It will also grow golden brown when it grows dormant in the winter. Nonetheless, it is still the highest-ranking St. Augustine cultivar when it comes to cold tolerance.
It will become low-maintenance once it establishes its roots. Wear and disease resistance is relatively fair but all in all, it is a good choice for residential and commercial uses.
Which St. Augustine grass is best for shade?
Of the eleven cultivars of St. Augustine, there are actually four of them in the list of the best St. Augustine grass for shade: Seville, Palmetto, Bitterblue and Sapphire. Besides being tolerant to shade, they could also thrive well in full sun (four to six hours a day compared to Floratam who needs eight to ten hours a day).
Growing high-shade tolerant cultivars need specific maintenance practices though. One, it will compete with soil nutrients, water and oxygen and other plants in the turf so regular trimming of tree branches might be essential. Two, mowing height should be observed and three, foot traffic must be moderated.
Is St. Augustine a good grass?
Consistently making it to the top three grass types considered as best turf grasses is already enough reason why St. Augustine is a good grass.
Specifically, it is a good grass for four reasons: one, it is both drought and shade tolerant; two, most of its cultivars can thrive with the cold, with high color retention to last in the fall and to come back in full green speedier than others after the winter; three, it is relatively low-maintenance as soon as they establish roots; four, it is generally disease and wear resistant.
Is common St. Augustine grass good for lawns?
There is really not much difference between common St. Augustine grass from its cultivars.
It is fairly shade tolerant but unlike its cultivars, it is more prone to diseases like southern chinch bugs and leaf spots, among others. It also needs moderate fertilizing every now and then.
It will need a lot of watering while it establishes roots but soon after, it will generally be low-maintenance. So back to the question if the common St. Augustine grass is good for lawns, yes, it is. And not just for lawns actually, but as forage grass too.
What grass can I mix with St. Augustine?
There are only a few grass types that you could mix with St. Augustine to have a continuous dense turf that is drought, shade, high foot traffic and wear tolerant.
These grasses would be seeded Bermuda (never hybrid types), buffalo grass and zoysia. Mixing St. Augustine with other grass types besides these cannot be recommended as they would spark over-seeding, hence, higher maintenance requirements.
How to grow and care for St. Augustine grass
Unlike all other warm-season grasses that are grown through seeds, St. Augustine is not one of them.
For this grass, the vegetative process is used, which means that you can plant St. Augustine grass using plugs or sod.
For the entire sod to cover the turf, you will need much watering and fertilizing for the next four to six months. After the roots are established by the eight month, you need to proceed to the ‘care’ part.
Mowing
St. Augustine needs to be frequently mowed. It needs to be kept at 3-4 inches long or else, the grass blades will grow thinner in time.
During the summer you might need to mow every two weeks and less frequently during the spring and the fall. If it is grown in cooler climates, wait for it to green up after dormancy before mowing.
Aeration
We all know that it grows dense and this is the reason why you need to have an aerator because you will have to do this once a year, during early spring. But of course, with specific considerations.
Wait for the turf to turn 75% its full color and at a temperature higher than 65 degrees.
Dethatching
Minimal thatch is good for growth but we all know that when it gets too much, it brings more bad than good.
Dethatching it in spring is the most recommended but you have to mow the turf first at about 2inches. And after dethatching, you need to water the entire lawn.
Fertilizing
This process is also done during spring. You need to maintain the right pH level for the soil and adding iron fertilizer every now and then is also good. During its early growth stage, it needs to be fertilized every 6-8 weeks too.
St. Augustine grass diseases & problems
St. Augustine grass turning yellow
There are three major reasons that would explain why your St. Augustine grass is turning yellow: one, the soil is lacking nitrogen; two, it is experiencing root rot due to fungi; three, chinch bug infestation. When this happens, an all-around solution would be an iron-nitrogen solution or herbicide.
St. Augustine grass brown patch and how to treat
The brown patch disease is a common summer disease when the temperature rises to more than 65 degrees. It is caused by a large brown fungus called rhizoctonia.
It mostly harms the crown of leaves but does not reach the base. To treat this, applying a potent fungicide would be the intervention.
Dead spots in St. Augustine grass
Dead patches are often caused by insects, specifically chinch bugs. They love niching on the base of the grass’ stem.
It causes yellow patches at first and when uncontrolled shall wear down into dead spots. Applying mulch in the turf would do the trick.
Purple tips on St. Augustine grass
Do not be super alarmed when St. Augustine starts developing purple tips. This is just a normal reaction of grasses when they are under climate stress meaning that they are still adjusting with sudden ups and lows in climates.
All you have to do when this happens is to trim the purple tips and apply a good herbicide.
How to make St. Augustine grass spread quickly
Compared to Bermuda, St. Augustine has a slower growth rate. To make the grass spread quickly, it is advised for you to plant plugs or sods during the summer using the right type of soil (sandy, clay with pH levels from 5.8-8).
Make sure that it is also well-aerated and follows a frequent watering schedule for faster root establishment and foliage development. Adding nitrogen, iron and phosphorus should be the final touch.
St. Augustine grass vs Bermuda grass
These two are the most popular seed/sod choices out there. While they can be mixed as turf grass, most people choose only one especially in re-sodding.
There are stark differences between these two though:
- St. Augustine is shade resistant, Bermuda isn’t;
- Bermuda can go through the summer without so much water but St. Augustine can’t;
- St. Augustine needs intensive fertilizing while Bermuda isn’t;
- Bermuda can tolerate high foot traffic while St. Augustine can’t.
St. Augustine grass vs Zoysia grass
Zoysia is also a popular turf grass choice like the St. Augustine and they too have considerable differences: color, maintenance, cost-efficiency and recuperative potential.
- Zoysia has a deep to pale green color while St. Augustine has deep green to blue green color.
- Zoysia requires more maintenance, detailed care and frequent watering and fertilizing while St. Augustine requires less.
- St. Augustine is cheaper when it comes to sods, sod installation and maintenance while zoysia is expensive.
- Zoysia only turns green after the winter during late spring while St. Augustine can do so as soon as the temperature rises above 10 degrees.
St. Augustine grass vs centipede
Both grass types have V-shaped leaf blades; only the centipede grass has thinner and more pointed leaves.
St. Augustine has more care requirements because it has more cultivars. Specifically, centipede is more cold tolerant than St. Augustine but the latter is more shade tolerant than centipede. Both are aggressive growers, though.
In terms of diseases, centipede is susceptible to grubs and nematodes while St. Augustine is vulnerable to brown patches and chinch bugs.
Conclusion
To conclude, there is a lot to know about St. Augustine. For one, it has cultivars with specific characteristics and needs that must be considered.
Aside from this, it also has growing and caring requirements like all other grasses regardless of how tough it could be. But given the profile of St. Augustine written here, it is a good grass to be used as turf cover and more.