Fairy Rings

All types of lawn and grass can be affected by fairy rings, which are most obvious during the summer months. Infection will be present in the soil from one year to the next, and the rings will gradually become wider each year. The symptoms vary according to the fungi responsible, and may appear as rings of dead grass, rings of dark green grass or rings of mushrooms and toadstools. 

Fairy rings may be classified into three main types:

Type 1 have a ring of dead grass bordered on both sides by greener grass. Mushrooms and toadstools are often found in these rings. The mycelium of the fungus is water repellent, so in drier weather the grass dies off due to a lack of water. The dead grass releases nutrients as it decays, so the adjacent grass appears dark green and healthy. 

Type 2 have a ring of actively growing darker green grass with or without mushrooms and toadstools 

Type 3 have a ring of mushroom or toadstools but no change in the colour or growth of the grass.

Controlling Type 1 fairy rings is not straightforward. Spiking and the application of a wetting agent will help break up the water-repellent properties of the mycelium and aid water penetration. Professional fungicides are available, but success is not guaranteed. Spiking, aerating and watering is often a more efficient means of controlling the rings then chemical intervention.

In extreme cases, the ring may be dug out by removing the turf and topsoil to a depth of at least one foot and either side of the ring. Care needs to be taken moving the soil away from the lawn. The area can then be filled with fresh soil and reseeded.

Type 2 fairy rings may be masked by keeping the lawn well fed with nutrients, so the colour of the ring blends into the overall rich green of the lawn.

No remedial action is needed with Type 3 fairy rings.