Without proper care and maintenance, a St. Augustine lawn can develop brown dead spots all over the yard. Pest infestation, excessive fertilizer application, and turf diseases can make your lawn turn color and appear dead, but there’s something you can do to revive the grass.
The easiest way to revive St. Augustine grass is to water your lawn enough, get rid of pests such as grub worms, and improve soil quality. Enough water helps grass survive the drought that’s common during summer, while grub control prevents root damage that usually kills grass quickly.
Why did my St. Augustine grass die?
Lack of water, diseases, and unhealthy soil are the major reasons St. Augustine grass fails to thrive. While it is possible to bring back grass that’s been dead for a short period, you need to first identify the cause of the problem.
Here’s why St. Augustine grass dies in your lawn:
Various diseases can be the reason why your grass is dying or appearing as though it is dead. St. Augustine grass is prone to some diseases such as brown patch disease, gray leaf spot, and take-all root rot.
Brown patches of dead grass usually start appearing during fall and spring when the weather is warm and humid. These conditions are favorable for the spread of brown patch diseases in St. Augustine lawns.
In the days of summer when the weather is warm or hot, gray leaf spot may invade your lawn and exhibit signs such as purple to brown spots that eventually grow into dead patches as the disease spreads.
If you do not treat your turf when you see symptoms of these diseases, you’re likely going to end up with dead spots that appear brown.
Excess fertilizer application
Another major cause of dead St. Augustine grass is too much nitrogen fertilizer. During spring, homeowners start a lawn maintenance program. Most of them push their lawns to make the grass spread faster and grow thick and dense.
If you end up applying too much nitrogen fertilizer to make your grass grow quickly, you risk burning your lawn. You’ll start to notice signs of brown patches that may turn out to become dead spots.
The good news is, these brown patches of St. Augustine grass can be revived easily.
Pest damage is one of the most common reasons for dead St. Augustine grass. Grub worm infestation is one common problem in lawns from during summer through early fall.
White grub worms eat the roots of your grass causing it to die from the inability to draw water and nutrients from the soil. You can apply a grub control pesticide from spring to control grubs.
Another common problem in St. Augustine grass is chinch bugs. These infest southern lawns a lot and can cause damage that manifests as “irregular-shaped areas of dead and dying grass that result from chinch bug feeding.”
Most cases of insect damage in lawns can be fixed if intervention is done early. You can start reviving St. Augustine grass lawns by getting rid of grubs and chinch bugs as soon as you notice the symptoms.
Summer often comes with drought. If you depend a lot on rain to water your lawn, you may experience dead grass when drought comes. This is called drought stress.
St. Augustine grass thrives well when watered a few times a week. If it goes about 6 weeks without water, it will turn brown and appear to be dormant and dying.
If you’re not too late, you may be able to revive your turf and bring it back to life just by watering it adequately using a good sprinkler that sprays water evenly.
Poor soil quality may be the reason why St. Augustine turf is dying. Having a thin layer of topsoil with gravel, rocks, or heavily compacted clay soil beneath can be a real problem for turfgrass.
The roots fail to grow deep enough to support healthy growth and development of the grass, and any nutrient and water deficiency will start manifesting as wilting and dying grass.
Soil remedy can easily revive the lawn and bring it back to life, but you may need to start with a soil test to know the deficient nutrients and what type of soil you may need to install in your yard.
Can dead St Augustine grass come back?
You can easily bring back St. Augustine grass that looks dead to a lush green and dense lawn. However, it will depend on the cause of its browning.
A lawn that appears to be dead over a period of 3 to 5 weeks can be revived. If it remains dead for too long, you may not be able to bring it back to life because it will be dead to the roots.
Before tearing your lawn apart to grow a new one, you may need to examine it to see if the grass is truly dead or is just in a dormant state that can be revived.
How to revive St. Augustine Grass
St. Augustine grass that appears to be dead for less than 5 weeks can be revived depending on the underlying problem.
Here’s how to bring back dead St. Augustine grass and make it grow green again:
1. Water your lawn adequately
Extended periods of hot and dry weather, St. Augustine grass might start to die. The best way to bring it back is to start watering it about 3 times a week.
Water the turf deeply to achieve the right amount of water your turf needs. St. Augustine grass requires approximately ¾ inch of water two times a week. If you water adequately to bring it back to life, you may need to do a total of about 1 ½ inches of water every week.
However, if the lawn is totally dead due to drought or lack of water, you might not be able to bring it back to life.
Will watering brown grass make it green?
Try watering the dead grass deeply to reach the roots. This should regrow the grass especially if it is the type that has rhizomes running deep in the soil. You should be able to see the grass growing back and starting to turn green after 3 to 4 weeks.
While watering grass that’s been dead for about 1 to 3 weeks can bring it back, it may be difficult to bring back dead St. Augustine grass that has been in that state for over 5 weeks.
2. Improve soil quality
If your St. Augustine turf is dying because of poor soil quality, the solution is improving the quality of the soil to make sure it is suitable for this type of grass. St. Augustine grass likes to grow in well-aerated soil so you might want to address soil compaction and deep thatch in your yard.
Here are a few steps you can take to improve soil quality and revive St. Augustine grass:
- Examine the yard to make sure you have an adequate layer of potent soil for the roots to grow deeper for a healthy lawn.
- Do soil tests to determine the composition and the nutrients needed. You’ll need to make sure your lawn has around 5% organic matter to bring back dead St. Augustine grass.
- All a little topsoil on the lawn and water it to provide nutritious ground for the grass to grow.
Fixing the soil in your yard goes a long way in maintaining a healthy lawn. Clay soil can be a major culprit that causes dying grass, especially during drought. Ensure it is well aerated to help the grass survive.
3. Dethatch the lawn
A thick accumulation of thatch in St. Augustine grass can cause suffocation and the slow death of grass. Thick thatch is a good habitat for insects and disease-causing agents. It leads to shallow roots and winter kill.
To try and revive your lawn, dethatch it to allow easy nutrient supply when feeding. In addition, you may need to aerate to prevent root suffocation that may be causing your grass to die.
4. Reseed the lawn
As the grass dies, it starts to form bare spots. In most instances, extensive lawn damage may not be repairable. The solution may be tearing down the lawn and starting afresh.
However, for bare spots, rake over the dead grass to loosen and remove it, and then go ahead to fill in the bare spots. You can do this by reseeding with new grass seed, feeding and watering for proper growth.
Here’s a great video to help your lawn back to life:
- Texas A&M University Agrilife Extension: Chinch Bugs in St. Augustine Lawns
- University of Florida IFAS Extension: Gray Leaf Spot of St. Augustinegrass: Cultural and Chemical Management Options
- Oregon State University, OSU Extension Service: Why Is My Lawn Dead?
- Michigan State University, MSU Extension: Winterkill of Turfgrass (E0019TURF)