Pink lawns are on the increase this year, according to the news. The latest snowfall has covered our lawns and then disappeared to reveal a different style of grass! Many lawn enthusiasts are very upset, while pink fanatics may think it looks quite cool.

It is not vandalism, nor is it a new breed of grass, it is in fact a fungus called Microdochium nivale which is also known as Fusarium Patch or

Pink Snow Mould . It develops when the lawn is covered in snow, which causes the grass to virtually suffocate. You may not notice the fungus straight away, but after about a month it will be apparent. I say this because fungi produce a tiny hair-like material called Mycelium. At first this will not be visible to the naked eye, as it is thinner than a spider's web. As the Mycelium grows and groups together it will be easier to see, especially when the grass is wet, eg in the morning after a cold damp night. In this particular type of fungus, the Mycelium will be pink.

Also, in many types of fungi a protective coat called Sclerotium is found. These are the size of pin heads and protect the fungus from drought, hot rays from the sun, among other problems. Normally though, they do not develop for a few months and sometimes not at all. Pink Snow Mould does not produce Sclerotium, but millions of spores instead. These spread, causing the fungus problem to increase. This is why this particular type of fungus is visible after about a month, unlike others which can take much longer. I will cover another type later on.

To eradicate this problem, there are a couple of treatments that can be applied. The best option is to use a fungicide. There are some which cannot be applied at this time of year as they will not work if the temperature is too low. There is a fungicide with a chemical in it called Trifloxystrobin, which can be used all year round and is recommended for use on Snow Moulds. It is best to choose a dry day for applying, remembering to read all instructions before use. This one is best for use on home lawns, but there are others which are available for commercial and agricultural use.

If you are not keen on using chemicals, like myself, there are other methods which may not be as effective but should work for the short term. The first is to rake out the Mycelium and dispose of it effectively eg by burning. The second is to
aerate twice a year. Aerating provides important benefits to your lawn, and though it can be a tedious job it is worth it in the long run. Also, by applying fertiliser twice a year, it will help to keep the grass healthy and disease free. It is best to apply fertiliser after aerating as it goes directly to the roots, as well as the top of the lawn. There are many types of fertiliser on the market, so it is important to seek advice if you are unsure which is the best for the time of year.

There may be areas of the lawn which will not re-grow after suffering the fungus problem. These will need digging out and either re-seeding or turfing, according to the time of year.

Apart from Pink Snow Mould, there is another fungal condition called
Grey Snow Mould . It is very similar and shares the same common names (Fusarium Patch or Snow Mould), but the hair-like webs are grey in colour. The patch affected is a tanned colour with grey mycelium on the outside. Also, Pink Snow Mould is much quicker to develop than the grey type, which can take three to five months before appearing. The same principle as I have talked about above should be used to eradicate it.

However, there are other similar lawn problems which will probably need a specialist opinion. If you are in any doubt then consult an expert before using chemicals or digging your lawn up!

This is the worst year for Snow Mould though. According to the

Met Office this has been the worst cold spell for 30 years! Weather like this is bound to have an effect on many of our lawns and plants.
Let's hope the summer is a warm one!

Nigel's Gardening Hints and Tips
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