Water in the morning or midday so that the leaf blades dry as quickly as possible. Avoid excessive applications of nitrogen fertilizer. This induces tender, succulent growth and causes more need to mow and more chance for infection. Never apply more than 4 pounds of nitrogen per 1,000 square feet in an entire year. Chemical Control Severe disease may warrant a fungicide.
Chemicals are most effective when combined with cultural controls.
Be sure to follow the instructions on the fungicide label for specific rates and time of applications. 1 Colorado State University Cooperative Extension plant pathologist and horticulturist, Integrated Pest Management Program, Jefferson County. Go to top of this page. Updated Wednesday, May 02, 2001. Contact Cooperative Extension Web Manager .