How to Troubleshoot White Mildew on Grass
White mildew on grass is the result of the fungus Erysiphe graminis, commonly known as powdery mildew. Kentucky bluegrass is particularly susceptible to it, although zoysiagrass, fine leaf fescues and Bermuda grass are also susceptible. Powdery mildew attacks the surface of the grass and can eventually cause the leaves to turn yellow, and the lower leaves may die. In extreme cases, the entire plant may die. Does this Spark an idea?
Instructions
-
-
1
Allow sunlight to penetrate the area, as powdery mildew flourishes in areas with dense shade. Use pruning shears to cut back shrubs and tree limbs that prevent sunlight from reaching the ground in areas where white mildew appears on the grass.
-
2
Improve air circulation. High humidity and poor air circulation create the perfect environment for powdery mildew to flourish. If the grass is part of a landscape made up of dense shrubs and flower plantings, thin the existing plantings or remove the grass and replace it with mulch or a ground cover.
-
-
3
Don't mow your grass too short. The University of New Hampshire Cooperative Extension Service recommends leaving some extra growth on grasses that are susceptible to powdery mildew.
-
4
Use chemicals sparingly. It is often possible to control powdery mildew without the use of fungicides. If you do decide to apply a fungicide, one application of Mancozeb or Bayleton is often sufficient, although you can safely apply these chemicals two to three times at four to six day intervals to treat severe cases.
-
1
Tips & Warnings
If powdery mildew affects a particular area repeatedly, consider digging out the grass and replanting with a resistant variety, or choose a different type of plant as a ground cover.
Use caution when using fungicide. Read the label carefully, and follow the manufacturer's directions, including for storage and disposal.
References
- Photo Credit lawn image by Allyson Ricketts from Fotolia.com
