Proper fertilization, mowing and watering helps fescue lawns withstand disease. It is always better to perform proper maintenance to prevent diseases than use fungicides.
Fescue yards are subject to four common diseases, including:
1. PYTHIUM BLIGHT – This occurs late in the spring when there are hot days, warm nights and plenty of rain. A white growth will begin at the edge of a dead patch. It is commonly seen on lawns which have had too much seed planted in the fall or spring. Too many new seedlings allow the disease to kill large patches. Fertilizing heavily in the late spring causes verdant growth for the fungus to grow on. Pythium blight can be controlled with fungicides. Controlling it by careful seeding and fertilizer is better.
2. BROWN PATCH – This is most common on fescue fertilized when night temperatures are above 68 degrees. The dead sections start small but can grow together. Do not fertilize fescue heavily in summer and irrigate in the late evening. There are fungicides available to help control it. Be sure to read the label and use the rate and timing as instructed.
3. SLIME MOLD – This is an amazing disease. It looks like oil has been poured on a table sized area of grass. The fungus grows on blades of grass and is gray then turns black. The fungus does not kill the grass. It can be washed off with a garden hose. No fungicide is needed.
4. DOLLAR SPOT – This happens when nights are cool and days are warm. It is linked to a lack of fertilizer and dry conditions. To control it, apply a judicious amount of fertilizer and water deeply once a week. There are fungicides available to help control it. Be sure to read the label and use the rate and timing as instructed.
Applications for Fescue
Perfect conditions for disease to develop include tight time lows are now over 65 degrees and the days are hot. Here are a few tips on how to fight back:
1. Put a preventative fungicide treatment down. This treatment can save a fescue lawn that gets heavy Brown Patch disease. Treatments last about 28 days and should be applied 3 times a year.
2. If a spider web looking fungus is found on the lawn in the early morning – treat it before it spreads.
3. Do not irrigate more than 2 to 3 times a week. Only water starting around daylight.
4. Make sure mower blades are sharp. Dull blades tear the blade, leaving it vulnerable to disease.
5. Do not use heavy nitrogen fertilizer during the late spring or summer. Extra nitrogen helps spread disease.
For fescue, the tough months are June, July and August. To keep the lawn looking as good as possible through the summer, fungicide treatments will be necessary. Without fungicide treatments, fescue will suffer.
Although they are effective, they can be costly. A fungicide costs about $20 per 1000 square feet per application. For a typical 5,000 square foot lawn, that comes to $100 per treatment.