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What Causes St. Augustine Grass to Turn Yellow? (2023)

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Yellow grass can be irritating! It isn’t easy to detect and can be similarly challenging to deal with. If you are managing yellow St. Augustine grass, maintain reading to read more.

Concerning St. Augustine grass

St. Augustine grass is a heat and also moisture forgiving grass that can be discovered in numerous yards in Florida as well as the other Gulf states. The blue green grass blades are coarse. This sturdy grass selection does not require a lot of water and is salt forgiving, making it the perfect grass for yards near the coastline.

Why does St. Augustine grass turn yellow?

Iron deficiency

What is iron chlorosis? Low iron degrees in the grass trigger iron chlorosis. A dirt pH degree that is also high makes it hard for the grass to soak up the iron in the soil.

Grass needs iron for chlorophyll advancement. Chlorophyll is what provides grass its wonderful green shade. Iron chlorosis is generally seen in St. Augustine grass in the very early spring. You can inform if your grass has iron chlorosis due to the fact that the grass blades will have stripes of yellow and also environment-friendly on the grass leaf.

Nitrogen shortage

St. Augustine grass that is deficient in nitrogen will have solid yellow blades of grass that are transforming lime green. Usually, grass will come to be nitrogen lacking after a whole lot of rain or overwatering during the summertime. The excess wetness leeches the nitrogen out of the soil.

Take-All Root Rot (TARR)

Take-All Root Rot (TARR) usually appears in the spring if soils are as well alkaline. There will be yellow patches with eco-friendly and yellow grass blades. If you believe TARR, draw out a glob of grass If it is TARR, the grass will show up conveniently, and also the roots will be brief as well as dark.

Exactly how do I take care of yellow St. Augustine grass

How Do I Fix Yellow St. Augustine Grass

What can I do? There is a service to every of these issues to reverse yellowing St. Augustine grass


Soil compaction can make it tough for grass to absorb all the water and nutrients it requires. Aeration punches openings right into the grass, enabling air and water to get to the plants’ roots. The best time to freshen remains in the springtime.

Iron applications

If the problem is a lack of iron or iron chlorosis, the option is as simple as an iron application. Spray a chelated iron solution onto the grass Prevent watering till a minimum of 24 or after application.

Nitrogen fertilizer

Give your grass an increase of nitrogen with a nitrogen-rich fertilizer. I recommend a nitrogen application in very early summer season, an additional one in the middle of the summertime, and also round off the growing period with a final application of nitrogen. St. Augustine grass typically does best with a half-pound to a complete extra pound of nitrogen per 1,000 square feet per application.

Peat moss

A healthy dose of sphagnum peat moss is the ideal remedy to TARR. The peat moss will encourage the development of valuable germs and reduced the pH of the dirt. Apply one to 2 bundles of peat moss per 1,000 square feet of grass. After application, extensively saturate the peat moss with water.


If you can not beat TARR with a peat moss application, try a fungicide spray. Use it to the affected areas. Many fungicides work for concerning one month.

Last thoughts

Don’t let yellow St. Augustine grass ruin your yard! Identify and treat your trouble. Enjoy your environment-friendly grass once more!

Avatar for Mutasim Sweileh

Mutasim Sweileh

Mutasim is a published author and software engineer and agriculture expert from the US. To date, he has helped thousands of people make their yards lush and thick.