Advice
RHS Help & Advice
Dead patches on lawn
These are many reasons why these may occur and the most likely are not usually due to pests or diseases. The most common causes are:
- Petrol spills or leaks from the mower.
- Uneven application of weed killer. Weed killer damage
- Uneven application of fertiliser.
- Inadequate preparation before sowing grass seed may mean there is buried debris or an uneven surface. Lawns from seed or turf
- Badly laid turf or uneven surface. Lawns from seed or turf
- Uneven surface is 'scalped' while mowing. Autumn lawn maintenance
- Waterlogging: attend to drainage.
- Drought: water; grass will recover after a wet spell. Water conservation in the garden
- Excessive thatch: Scarify.
- Autumn lawn maintenance
- Overuse.
- Bitch marks: douse copiously with water as soon as possible
Diseases
Newly sown grass: seedling blights, similar to 'damping off'.
Established lawns:
- Fusarium patch or snow moulds are prevalent in cold weather.
- Brown and yellow patch, take-all patch and red thread are prevalent when conditions are warm.
- Leaf spots and other fungi may also cause dead patches.
Pests
Chafer grubs
(right) cause problems between autumn and spring. These fat C-shaped
grubs are creamy white with brown heads.
Leatherjackets (larvae of crane flies/daddy longlegs) are at their most damaging in midsummer, but can become a problem in late winter after a mild winter. They are greyish brown legless maggots up to 45mm (1.75in) long, that eat grass roots.
Prevention
Good lawn care encourages healthy, vigorous growth, which is resilient and less susceptible to disease.
Autumn lawn maintenance
For more information on this topic click on Autumn lawn maintenance or visit the BBC gardening website