Commonly grown in Texas, Houston, Mexico, California, the Louisiana, the St. Augustine grass although beautiful is typically faced with the following problems:
A yellow St. Augustine grass problem is a strong indicator of low iron levels in the leaf tissue or nitrogen deficiency. To correct this, apply iron and it should be corrected.
Lack of nitrogen fertilizer can also lead to yellowing grass. This yellowing is different from iron chlorosis in that there will be no parallel stripes of yellow and green on the grass blade. Instead, the grass blade will be solid yellow in color. The most effective way to solve this issue, as well as the iron chlorosis issue, is to apply a combination of nitrogen-iron product such as Iron Plus (CHECK ON AMAZON). If you want to use Green Sand (CHECK ON AMAZON), just make an application of a slow-release lawn fertilizer such as 19-5-9 after the Green Sand is applied. Water thoroughly after applying.
Another cause would be TARR (Take-All Root Rot) and is characterized by yellow and green grass in your lawn. However, upon close examination of the stolons (runners), you would find short, dark brown to black roots. You should apply sphagnum peat moss (CHECK ON AMAZON) to get rid of this problem. Apply approximately 1 to 2 bales of the peat moss per 1,000 sq. ft. to the affected areas of the lawn. Then thoroughly soak the peat moss until it is wet.
St Augustine Grass Yellow Streaks and Spots
If there are yellow spots on the blades of your St Augustine grass then your lawn is probably suffering from Iron Chlorosis.
An evidence of this would be yellow-colored spots and streaks on the blades of your plant.
This typically happens when your soil lacks iron and is most evident in summer months as the grass is unable to absorb iron as fast as it grows.
Iron Supplement for St.Augustine grass
You should provide your lawn with an Iron form that can be easily absorbed. Iron Chelate and Iron sulfate works magic on your lawn!
Using this, you not only add more Iron into the soil but you’re able to release the Iron present in the soil as it’s acid-forming.
The easiest and best way to fix the Iron deficiency in your soil is by adding Iron supplements or Iron sulfate all through the year. Adding it once off would not produce the desired results.
You should add acid-forming fertilizers with Iron content to the soil once every 2-3 months. Do that at least twice each week and your lawn would turn out fine.
Milorganite works awesome. It is a slow-release fertilizer. If your lawn is of average size, you may use 5-10 bags of Milorganite for best results.
That is, you may want to use 50-100 pounds of Milorganite per 1000 sq. feet of the lawn.
St Augustine Grass Yellow In Spring
Rains are responsible for St. Augustine grass turning yellow in spring. Rains will leech out the Nitrogen from the soil, Then the grass in your lawn will turn yellow due to Nitrogen deficiency.
Water-logged soil also prevents the grass from takin in the needed nutrients. To correct this problem, apply some Nitrogen fertilizer (CHECK ON AMAZON) in August. That will help revive the Nitrogen-deficient soil.
If your grass turns yellow, it’s a clear sign of a fungal infection. You should apply fungicide to treat the grass.
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St Augustine Grass Yellow Circles
Different fungi affects St.Augustine grass. One sign of fungal infection is yellow circles on grass blades. These types of diseases are typically seen on a part of the lawn.
One of these is the Take-all root rot, caused by a fungal attack. Excessive rains and overfertilizing are common causes of this infection.
You’ll need to spray a fungicide on the infected areas of the lawn. The best period to apply this fungicide is in fall and spring.
Myclobutanil (BUY ON AMAZON) and Azoxystrobin work wonders on Take-all root rot. Mix 1/2 ounce of water in 4 gallons of water and apply this mixture on 1000 sq. ft of lawn.
Apply this fungicide mixture to your lawn on a windless day. Two applications 28 days apart would suffice. Spray in spring and fall.
St Augustine Grass Turning Yellow in Summer
St. Augustine lawns suffer at the hands of Chlorosis during summer months. Lack of Chlorophyll caused by high temperatures will prevent your plants from absorbing the basic nutrients such as Iron and Nitrogen which translates to Chlorosis.
You can then proceed to add some organic matter to bring down PH and increase nutrient absorption by the grass. I recommend adding in a layer of acidified compost, then add liquid seaweed with Iron.
St Augustine Grass Yellow After Fertilizing?
If your St. Augustine lawn recently turned yellow after feeding it then it could be a sign of overfertilizing. In fact, too much fertilizer can cause harm too.
What happens is that the excessive nitrogen fertilizer would burn the grass blades (a process known as leaf scorch). The grass yellows at the bottom and then turns brown at the top.
This happens only with quick-release fertilizers. That’s why it’s better to use slow-release fertilizers like Milorganite.
Simply water the lawn thoroughly. That will help wash away any excess salt present in your soil.
Rake and Till the affected area.
Resod your lawn if a large part of the lawn is affected.
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Chinch bugs are a common pest of St.Augustine grass. Patches of dead grass surrounded by a circlet of yellow grass is a sign of Chinch bug infestation.
What causes Chinch Bugs?
A layer of dead organic material (or thatch) in your lawn will cause a Chinch bug infestation.
To correct this, use a turf aerator to punch holes into the lawns and increase air movement in the lawn. That also helps in the prevention of a Chinch bug infestation.
There is a cultivar of St.Augustine grass that is resistant to Chinch bug infestation called ‘Captiva’. This cultivar is hardy in US Zones 8b-11.
Does Triazicide kill Chinch Bugs?
Spot spraying the affected areas with Triazicide would work effectively. Inspect the affected area every 3-5 days to make sure the treatment is working.
Why is my St Augustine Grass Turning Light Green?
Low iron levels in the leaf tissue or nitrogen deficiency will cause your plant to turn light green. Supply them with nitrogen (CHECK ON AMAZON) once every 3 months and they should turn out fine.
Why Is My St Augustine Grass Dying?
Lack of nutrients, water, diseases, and unhealthy soil are some reasons why your St Augustine plant may be dying.
How To Revive St Augustine Grass?
To revive your St. Augustine grass, water it with 1-1.5 inches of water per week. After that, apply nitrogen fertilizer (CHECK ON AMAZON) and grub control, then mow the lawn high at 3 inches to ensure the grass becomes green again.
If the grass is dead, install new sod to revive and bring the lawn back to life.
How to fix Overwatered St Augustine Grass?
Aerating and de-thatching your yard is a sure way to fix an overwatered lawn.
Why my St Augustine Grass Turned To Straw?
Lack of water or water-clogged grasses will slowly begin to turn to straw.
Why is My St Augustine Grass Turning Brown?
The application of too much nitrogen fertilizer will cause your grass to turn brown. Water off the fertilizer to correct this.
How to Get St Augustine Grass to Spread?
- Augustine grass spread fast and grow thicker if you plant sods in early summer in well-draining soil with a pH range of 5.0 – 8.5.
- Then Apply a phosphorus fertilizer
- Water lightly twice a day for the first 14 days.
Best Fertilizer for Yellow St Augustine Grass in California, Houston, Louisiana, Texas
The best fertilizer for St Augustine grass is one that has one pound of nitrogen for every 1,000 square feet of sod and they include:
- BEST OVERALL: Scotts Southern Turf Builder Lawn Food
- BEST BANG FOR THE BUCK: Pennington 100536576 UltraGreen Lawn Fertilizer
- BEST WITH SPRAYER: Simple Lawn Solutions Commercial Grade Lawn Energizer
- BEST LIQUID: Simple Lawn Solutions Maximum Green Liquid Fertilizer
- BEST NATURAL: Milorganite 0636 Organic Nitrogen Fertilizer
- BEST SOD STARTER: Pennington UltraGreen Starter Lawn Fertilizer, 14 LBS