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Is Your St. Augustine Turning Yellow? It could be Chlorosis.


Is your lawn St. Augustine lawn turning chartreuse or yellow or brown?

With the higher temperatures of summer, a common issue in St. Augustine lawns is chlorosis. Chlorosis is a lack of chlorophyll caused by a deficiency of much-needed nutrients such as Nitrogen and Iron. When soil temperatures and pH are too high, it’s difficult for lawns to take up these nutrients, even if they are available in the soil. Soil compaction and poor soil health also contribute to the problem.

By feeding the soil and stimulating microbial growth, your lawn can better absorb the needed nutrients, even during the summer months. Adding organic matter can help bring down the pH a bit, which helps with nutrient uptake.  If you are a Soil Building Program customer you’ll receive balanced feedings year-round.


Other Issues That Can Turn Your St. Augustine Yellow Or Brown

Fungus and Other Diseases

A large brown patch of grass, is most likely a fungal infection that causes St. Augustine grass to turn yellow or brown. It results from a fungal infection brought most commonly brought about by a fungus known as Rhizoctonia solani. It usually occurs in spring when the weather turns warm and humid. Your grass is especially susceptible where patches lay in moist, shaded areas.

To diagnose for disease, a simple check which includes, looking for rotten leaf sheaths and tugging on them – if the old leaf blades easily pull free from a light tug. You can prevent the infection by reducing nitrogen supplements to the lawn because nitrogen will encourage the growth of green blades usually attacked by fungi (causing the fungus to grow even more).

Preventing fungal diseases also includes applying fungicide in late fall before the grass becomes dormant and early spring before it starts to turn green. If you already have the infection or itshows during spring, you can treat it by applying fungicide or calling us to help at 972-272-9211.

Another fungal disease that could be causing problems for you St. Augustine grass is the Take All Root Rot caused by the fungi Gaeumannomyces graminis var. graminis. TARR doesn’t form circular patterns, it instead starts with changing the color of the grass to yellow to brown and black as the grass dies.

Having enough nitrogen concentration in the soil can prevent the Take All Root Rot disease from occurring. However, if you cut back on nitrogen fertilizers in late fall and there is heavy rain in winter, the Root Rot condition will be become worse. It’s best to treat Root Rot with a fungicide.

How Our Treatments Help Your St. Augustine From Turning Yellow

Our May-June lawn treatments are filled with liquid bio-stimulants, worm castings and micronutrients will help keep your lawn and landscape healthy and well-fed

In June-July, we add a dry organic fertilizer that will continue to feed the turf to alleviate any deficiencies that might persist through summer

Aerating soil is another great way to reduce soil compaction and boost microbial activity. Soil microbes break down organic matter and make nutrients available to your plants

If you are attempting to heal your chlorotic lawn yourself, we recommend adding a layer of acidified compost, or garden sulfur, to the area and apply liquid seaweed with added iron.

Since we’re obsessed with soil, let us do the work for you! Become part of our Soil Building Program today! It’s easy to get started. Follow the link here to get a free quote and we’ll email you an estimate. When you are ready, we’ll sign you up!

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Soils Alive is an active member of the Agronomy Society of America (ASA), Soil Science Society of America (SSSA), and Crop Science Society of America (CSSA).

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Soils Alive, Inc. has been a member and accredited business with the Better Business Bureau since 2004. You can find our listing here. We are presently an A+ rated business.

Member, Texas Nursery & Landscape Association

Soils Alive is a member of the Texas Nursery & Landscape Association(TNLA). TNLA is Texas' largest and most prominent green industry advocacy and governance group, and was set up to promote the landscape, nursery and horticulture industry in Texas. 

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We earned the 2014 Super Service Award from Angie's List. The award reflects consistent high levels of customer service. Check our reviews atAngie's List. We won the 2013 Super Service Award as well.

1821 Wall Street
Garland, TX 75041
Ph: 972.272.9211

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