Common Lawn Diseases: Redthread Disease
Redthread is one of our most common lawn diseases and it’s most often seen in autumn time.
This is what Redthread disease looks like.
Picture courtesy of the Turfgrass Growers Association
If you have noticed irregular shaped patches on your lawn that looked bleached and have a slight tinge of pink, then your grass is probably suffering from Redthread disease.
What causes Redthread Disease?
Redthread is caused by the fungus Laetisaria fuciformis. It rarely kills the grass – but it does make it look a bit odd for a while.
The fungus is present in your lawn all year round – but in such small quantities that neither you, nor your lawn will notice it all. However, if the conditions are right, the fungus will multiply and you will see it as tiny pink or red strands attached to blades of grass. It’s incredibly beautiful and very delicate – but not what you want in your lawn.
How to avoid Redthread disease
There seems to be a connection between Redthread disease and low nitrogen levels in the soil. It appears that if your lawn is hungry, it’s more likely to be affected by Redthread. That’s why it’s important to feed your lawn in spring and summer.
Don’t apply nitrogen to your lawn after the end of august – especially in Scotland – it will encourage lush growth at the end of the season, which often leads to a different lawn disease – Fusarium patch.
Redthread thrives in warm, damp weather. There’s nothing you can do to control the weather but you can take steps to make sure your lawn is well drained dries quickly after dewfall or rain.
Scarifying and aerating are important. These jobs can be done in either spring time or autumn time. Scarifying gets rid of the thatch layer that is notorious for affecting drainage. Aeration helps loosen the soil so that water can easily escape.
How to treat Redthread disease
There are very few chemical treatments available for domestic gardeners to use. You could contact a lawncare company and ask them to apply a fungicide. Alternatively, sit tight and wait for the frost to come. Redthread disappears as soon as the temperature drops and the grass will recover quickly next spring.
Come next spring – be sure to get a lawn feeding regime in place – that way you’ll avoid a repeat attack next autumn.