Diagnosing and Preventing Lawn Diseases

We checked the internet and believe we have pythium blight on our lawn. Do you have any recommendations?

The symptoms of many lawn diseases look similar. It takes a professional and frequently laboratory analysis to make a definitive diagnosis. Pythium is more likely to occur during warm humid weather and on overwatered and overfertilized lawns growing in shady areas. Patches first appears water soaked, turn tan or brown and the grass eventually collapses. A cottony growth may be seen on the dew covered grass blades in the morning.

Proper care is usually your best defense and control for this and all disease problems. Keep northern grasses 2 ½ to 4 inches tall, most southern grasses 1 to 2 inches tall and St. Augustine grass a bit taller, 2 to 3 inches.

If and when you water, water thoroughly enough to wet the top 6 inches of soil. Water only when the soil is dry enough that your footprints remain after walking across the lawn.

Avoid mowing and walking on wet turf which can spread the disease. The majority of your lawn fertilization should occur in fall. Avoid excess applications of fertilizer any time of the year but especially in spring.

Repeat applications of fungicides may provide relief. They can be expensive and the most effective products are usually not available to homeowners. Consider hiring a lawn care professional if proper care does not control this disease.