Battling Mushrooms In Your Lawn

Posted on: 14 January 2015

The small white or brown mushrooms that pop up in your lawn, commonly referred to as lawn mushrooms, can be a nuisance. The mushrooms are actually the fruiting body of a large fungal system that is growing just beneath the soil. Cultural control practices can minimize their growth and keep your lawn beautiful.

Find the Food Source

Mushrooms won't grow without a food source. The fungus feeds on decaying organic matter. Piles of pet waste or fallen leaves that need raking are the most common feeders for mushrooms. Maintaining the lawn and keeping it clear of debris helps prevent growth.

Not all food source is obvious. If your lawn is clean but mushrooms keep sprouting up, the food source may be buried. Usually you will find rotting wood, such as construction debris, an old tree stump or a dead root, several inches below the ground. The mushrooms will disappear on their own after the buried food source finishes decomposing. If the problem is severe, you can dig up the turf and remove the food source, but this is only necessary if your mushroom problem is severe.

Manage Moisture

Overly wet lawns are more prone to mushrooms than dry soil. For this reason, new sod is especially prone to mushroom growth because of its high irrigation needs. Mushrooms that only appear after heavy rainfall aren't a concern, because they usually disappear soon after the sun comes out.

Avoid over-irrigation to help control the mushrooms. Provide your lawn with only 1 to 2 inches of water two or three times a week, and only water when the lawn is in its active growth cycle. If the ground feels wet, hold off on watering until after it has had a chance to dry.

Open the Soil

Poor air circulation inside the soil can also increase the chances of mushroom development. A combination of dethatching and aerating helps open up the ground. Thatch is the thin layer of decaying grass that builds up directly on top of the soil. Some thatch is good, but if the layer is more than ½ inch deep you should remove it with a dethatching rake.

Aeration removes small plugs of soil from the ground, which loosens the soil and allows air and moisture to soak in. You can rent an aerator or dethatching rake, or hire a lawn maintenance crew to perform the service as part of your spring lawn care regimen.

Destroy the Evidence

Fungicides and chemical controls won't usually control mushrooms. Beyond removing the food source and managing moisture, there is little you can do to destroy the mushrooms. Fortunately, they aren't usually harmful to your lawn. When you notice the mushrooms coming up, rake over them to break them from their stalks. This prevents them from producing spores and spreading.

Like all mushrooms, lawn mushrooms can be toxic. Take precautions and keep your landscape maintained if you have pets or children. Wear gloves when handling the mushrooms, and never eat an unidentified mushroom.