Is There a Fungus Among Us?

If your lawn has suddenly developed brown patches, thinning grass, or strange discolored spots, you’re not alone. This week, Long Island is experiencing extreme heat, drought conditions, and humidity levels above 70%—the perfect combination for lawn fungus to develop.

Our cool-season grasses, including Kentucky bluegrass, fescue, and perennial ryegrass, thrive during the cooler months of spring and fall. Summer is stressful for these grasses. Naturally, they would prefer to slow down and go dormant until temperatures cool. As homeowners, however, we work hard to keep our lawns green throughout the summer, which can make them more susceptible to disease.

Good Fungus vs. Bad Fungus

Many people are surprised to learn that not all fungus is harmful.

Healthy soil is full of beneficial fungi, such as mycorrhizae and Trichoderma. These naturally occurring organisms form partnerships with plant roots, helping your lawn absorb water and nutrients while improving overall soil health.

Unfortunately, harmful fungi also exist. Under ideal growing conditions, healthy turf can usually resist these diseases. But when prolonged heat, drought stress, and high humidity combine, harmful fungi can quickly take over.

When nighttime temperatures remain above 70°F and humidity stays above 70%, lawns become much more vulnerable to diseases such as:

• Brown Patch
• Dollar Spot
• Red Thread
• Pythium Blight

How to Reduce the Risk of Lawn Fungus

Fortunately, there are several simple steps you can take to keep your lawn healthier during stressful summer weather.

• Water early in the morning. The ideal watering window is between 2:00 a.m. and 10:00 a.m. Avoid watering in the evening, as moisture sitting on the grass overnight encourages fungal growth.
• Mow high. Keep your lawn at 3 to 4 inches tall. Taller grass develops deeper roots and is better able to withstand heat and drought.
• Reduce excessive thatch. A thick thatch layer traps moisture and creates an ideal environment for disease.
• Aerate compacted soil. Aeration improves airflow, water penetration, and root development.
• Test your soil. A soil pH between 6.2 and 7.0 provides optimal growing conditions for most cool-season lawns.
• Limit nitrogen fertilizer during July and August. Excess nitrogen promotes tender new growth that is more susceptible to fungal diseases.

Natural Ways to Treat Lawn Fungus

If fungus appears, consider starting with natural treatments before reaching for harsh chemicals.

Baking Soda Spray

Mix:

• 2 teaspoons baking soda
• 2 teaspoons vegetable oil
• A few drops of mild liquid soap
• 1 gallon of water

Spray affected areas every 3 to 4 days to help slow fungal growth.

Neem Oil

Mix 2 tablespoons of organic neem oil with 1 gallon of water and spray infected areas every 7 to 10 days. Neem oil is a natural fungicide that can help reduce the spread of many common lawn diseases.

Think Before Using Chemical Fungicides

Many over-the-counter fungicides don’t just kill harmful fungi—they can also destroy the beneficial microorganisms your soil depends on. Repeated chemical applications may reduce soil biology and make your lawn less resilient over time.

Whenever practical, choose organic lawn care practices that support healthy soil. A living, biologically active soil is one of the best defenses against disease.

Don’t Forget Your Irrigation System

Proper watering is one of the most important tools for preventing lawn disease. An irrigation system that is programmed correctly delivers the right amount of water at the right time, reducing stress on your lawn while avoiding the excessive moisture that fungi love.

A beautiful landscape is an investment. Maintaining your irrigation system is far less expensive than replacing damaged turf, shrubs, or trees.

If you’d like to make sure your sprinkler system is operating efficiently during this summer’s heat and drought, we’re here to help.

Visit www.RainRich.com or call 631-423-2211 to schedule an appointment. We look forward to helping you keep your lawn healthy, green, and beautiful all season long.