Lawn Disease – Summer Patch

(Magnaporthe poae)

Summer Patch is a disease that occurs during warm weather and is caused by the fungus Magnaporthe poae. This lawn disease can be found throughout much of the United States, although it is more common in warmer climates. Summer Patch is often associated with shallow root systems due to poor soil conditions.      

Identifying Summer Patch -

This turfgrass disease forms circular patches that measure from several inches to several feet in diameter. The patches are bronze-yellow to straw colored. Grass leaf blades will turn yellow to brown, from the tip to the base, and the roots will turn moderate to dark brown.

The patches often form a “frog-eye” where less susceptible turfgrass species have survived inside the patch.

Conditions for Summer Patch Infection -

Summer Patch can only lead to an infection in your lawn if all of the following conditions are present:

1. Pathogen – Summer Patch (Magnaporthe poae)

2. Host – Multiple bluegrass species and fine fescue

3. Environment – Warmer climates with temperatures ranging from 70-80 degrees Fahrenheit and compact soils with high moisture levels and poor drainage

Summer Patch Control -

Cultural disease control practices create favorable conditions for a healthy lawn, and often create unfavorable conditions for the growth of Summer Patch. Environmental conditions cannot be changed, but cultural practices performed by the homeowner can be modified to lessen the chance of extensive damage from Summer Patch. Scotts LawnService can help determine a plan for preventing and controlling Summer Patch in your lawn.

For Summer Patch control and treatment, Scotts recommends the following cultural control tips:

  • Increase mowing height
  • Reduce soil compaction and thatch levels with core aeration
  • Lightly irrigate turf when temperatures are above 85°F
  • Improve the drainage of the soil
  • Fertilize with slow release forms of nitrogen to continually feed the turf but avoid rapid growth

Scotts LawnService has professional products that can prevent and control lawn diseases when cultural control practices are not effective.

Scotts LawnService is the trusted industry leader for professional quality lawn care. Our exclusive lawn care products include premium grass seeds and professional-grade fertilizers; our lawn service teams are comprised of highly trained, industry-certified professionals. Contact a representative today for Summer Patch control options available in your area and to learn how you can enjoy a lush, thicker lawn that only Scotts LawnService can deliver.