These can be very troublesome. Show as circles of lush green turf often surrounding dead or dying patches. The problem is mycelium. As the fungus, which creates the problem pushes the ring outwards, it leaves behind a white thread-like network, which prevents water penetration and dries out the soil. The green, lush section is the active fungus releasing and using the nitrogen in the soil.
The solution is deep spiking. Insert a garden fork right up to the shoulder – wriggle it. Withdraw and then repeat. When you have covered the area, copiously water it using a watering can. Fill with a mixture of water and a commercial detergent such as Teepol. This should work.
Fusarium Patch (Snow Mould)
A common disease, often occurring in autumn and spring. Shows as patches of yellowing grass, possibly edged with white or pink mould. Treatment is by brushing diligently to prevent surface moisture until the condition disappears.
To prevent a recurrence, avoid the causes of lawn compaction and spike it regularly. Dressing with iron-rich fertiliser is good, but avoid nitrogen fertilisers in late summer/autumn because they encourage the condition.
Pink and red patches, particularly after rain or heavy dew indicates this fungal disease. A feed with sulphate of ammonia may be all that is needed to get rid of it. Act quickly, it’s contagious and can be spread by mowing. Aerate, scarify and feed your turf to prevent a recurrence.
This slimy green or black mess on a lawn is found most frequently under dripping trees. It is also found on heavy, over mowed and rolled turf. Essentially a disease of impoverished, over compacted turf. Get rid of it by feeding and spiking.