There are several common lawn diseases in the UK, including Red Thread, Fusarium Patch, Dollar Spot and Rhizoctonia. Read more to find out how to identify and treat these common ailments.
Red Thread
Red thread is probably the most common condition that affects lawns in the UK. It is caused by a fungus and appears as circular patches of red-brown grass with a "thread-like" appearance. It develops in warm, moist conditions and can be treated by improving drainage, mowing higher, and using a fungicide. The fungus does not affect the root zone and the grass may show signs of recovery after a few days or weeks, even without any remedial action being taken. New growth should not be affected and new grass swards will be as healthy as before.
Fusarium Patch
Fusarium Patch is also caused by a fungus and appears as small, circular patches of yellowing grass. These patches can enlarge to form large, irregular shaped areas. It develops in damp conditions,mostly during autumn, winter and early spring. Fusarium Patch can be quite difficult to control as no chemicals are available for public use and are available only to professional lawn maintenance companies. You can reduce your risk of Fusarium Patch developing by ensuring the lawn drains rapidly after dews or rainfall, by improving aeration and drainage. This can be done by scarifying or spiking. You should avoid a high nitrogen in late summer and instead opt for a seasonal fertiliser that will help penetrate the roots.
Dollar Spot
Dollar Spot is caused by a fungus and appears as small, circular spots of yellowing grass that can merge to form large, irregularly shaped areas. It is likely to develop when day temperatures are high during summer months and conditions are humid. Heavy dews and thundery conditions can cause dollar spot to attack low fertility grass swards. It is most common in fescue dominant grass, as oppose to amenity grasses high in rye grass. Nitrogen rich fertilisers coupled with good drainage should reduce any risk of Dollar Spot occurring.
Rhizoctonia
This disease is caused by a fungus and appears as brown, circular patches of grass that can enlarge to form large, irregular shaped areas. It is sometimes known as root rot, because the fungus attacks the root zone, affecting the whole plant. You can reduce shading and improve soil aeration and drainage to help treat Rhizoctonia however the most effective method of reducing disease is by cultivating it and removing the area to break up the web underground and restrict it from spreading.
Although these are common diseases found in the UK they are not prevalent in every garden. The best treatment is prevention! By ensuring your lawn has good drainage and is aerated when required you should be lucky enough to avoid these conditions.