Fusarium - Snow Mould In Lawns. Advice and information.

Fusarium Patch disease is the most common of all lawn diseases in the UK.

It is recognised by the die-back of quite large areas of grass on compacted lawns in particular. Usually found in Autumn, but also in spring after there has been snow lying on the lawn for some lengthy period. It can spread and take hold under cover of snow - hence it's common name of Snow Mould.

Fusarium Patch disease starts as a small yellowing patch which turn brown as the patches enlarge. Sometimes - in damp weather - a white or pinkish mould can be seen in the patches. It normally subsides a little as the air temperature warms up and lawns dry out a little.

As with all diseases, it is much easier to prevent than to cure. Again it is proper lawn care and maintenance which is the answer.

Prevention of Fusarium Patch

Do NOT use feeds in late summer or autumn that have a high Nitrogen content - such are the spring and summer lawn feeds. Last feed with these should be early August at the latest.
Apply a heavy Potash based fertilizer in the Autumn. Liquid Tomato feed is good for this!
Spike compacted areas often through the year.
Don't walk over the lawn when it is covered in snow.

Treatment of Fusarium Patch Disease

Chemical treatment with Carbendazim - a systemic Lawn Fungicide as soon as you find the patches. Triadimefon may also be available, but the former is usually best.

Spiking, feeding well in the spring and summer and avoid over use (compaction) of lawns - particularly on heavy ground - in damp conditions. Treat at first signs.