Red Thread

Red Thread is a lawn fungus that commonly occurs twice a year: May/June and again in August/September. This type of fungus is caused by humid conditions and is much more common than you might think. Most lawns are likely to have experienced it at some point every year, possibly without anyone noticing. With Red Thread, the leaf dies off, though not the plant itself, and this gives the lawn a patchy look. If you look closer, you’ll notice pink threads about 2mm in length scattered throughout the grass.

Red ThreadRed Thread

The often-humid conditions experienced during May and June, along with mild weather, create the ideal situation for this fungus to develop. In hot weather it can be mistaken for drought, though wet conditions can also present the perfect circumstances for it to appear.

Some lawns may well be affected more than others. These can include: old lawns, or lawns that have been compacted; young lawns, such as newly laid turf that has not had the time to grow deeper roots and therefore increase resistance; stressed lawns (brought on by drought, heat or water logging); lawns that don’t experience enough air movement and hold onto dew; over-watered lawns (especially when watered in the evening during warm weather); and over-scarified lawn in the late spring (can weaken the grass and make it susceptible).

To manage this, the most important thing, as always, is good lawn maintenance. Mow your lawn regularly; make sure you remove clippings after you’ve mowed; and use a good quality, high nitrogen content fertiliser (such as our Hi-N Fertiliser that is high in nitrogen and promotes quick growth and root establishment – perfect for newly laid turf!).

If you suspect your lawn may be suffering form Red Thread, try to water less frequently in order to allow the grass to dry, don’t water in evenings and don’t scarify. Once you believe the disease to be under control, aerate your lawn and scarify, making sure to remove the thatch in order to prevent any further spread.