Common Summer Lawn Diseases and How to Prevent Them

Brown Patch

Caused by the fungus Rhizoctonia solani, Brown Patch thrives in hot, humid conditions.

Identification: Circular, brown patches of dead grass, often with a darker, smoke-ring border.

Prevention: Improve air circulation, avoid over-fertilizing with nitrogen, and water early in the day.

Dollar Spot

Caused by the fungus Sclerotinia homoeocarpa, Dollar Spot is common in lawns with low nitrogen levels.

Identification: Small, silver dollar-sized spots of bleached grass, often merging to form larger areas.

Prevention: Maintain adequate nitrogen levels, water deeply but infrequently, and improve air circulation.

Leaf Spot

Caused by various fungi including Drechslera and Bipolaris, Leaf Spot affects the grass blades.

Identification: Small, dark lesions on grass blades that may merge to form larger patches.

Prevention: Avoid excessive nitrogen fertilization, mow at the recommended height, and water deeply but infrequently.

Pythium Blight

Also known as "Grease Spot," Pythium Blight is caused by Pythium aphanidermatum and thrives in wet, poorly drained areas.

Identification: Greasy, water-soaked patches of grass that quickly turn brown and die.

Prevention: Improve drainage, avoid overwatering, and water early in the day to allow the grass to dry.

Proper Mowing

Mow at the Right Height: Maintain the recommended mowing height for your grass type to promote deeper root growth and reduce stress.

Keep Blades Sharp: Sharp mower blades ensure clean cuts, reducing the risk of disease entry through torn grass blades.

Avoid Mowing When Wet: Mowing wet grass can spread disease spores and create an ideal environment for fungal growth.

Adequate Watering

Water Early: Water your lawn in the early morning to allow grass blades to dry quickly, reducing the risk of fungal diseases.

Deep and Infrequent Watering: Water deeply but less frequently to encourage deep root growth and reduce surface moisture.

Avoid Overwatering: Excessive moisture promotes fungal growth. Adjust your watering schedule based on weather conditions.

Balanced Fertilization

Use Slow-Release Fertilizer: Apply slow-release fertilizers to provide consistent nutrients without promoting excessive growth.

Avoid Excessive Nitrogen: High nitrogen levels can make grass more susceptible to disease. Follow soil test recommendations for balanced fertilization.

Prune Trees and Shrubs

Trim back overgrown trees and shrubs to improve air circulation and reduce humidity around the grass.

Avoid Thatch Build-Up

Thatch, a layer of organic material between the soil and grass, can harbor disease organisms. Aerate your lawn regularly to reduce thatch build-up.

Soil Testing

Conduct regular soil tests to monitor nutrient levels and pH. Adjust fertilization and soil amendments based on test results.

Choose Disease-Resistant Varieties

When reseeding or planting new grass, choose disease-resistant grass varieties suited to your region.

Monitor and Act Quickly

Regularly inspect your lawn for signs of disease and take action promptly to prevent widespread damage.