Lawn diseases and pests
The database lists 5 problems recorded on this crop. 0 of them can cost the whole harvest, and 4 survive in soil or debris into next season — those are the ones that decide your rotation. The largest number are active in September.
Pressure through the year
The number of problems listed as active in each month. Pick a month to see what to sow, plant and harvest then.
Start from what you can see
What actually prevents them
Water at the base of the plant in the morning, never over the leaves. Splashing soil onto foliage is the delivery route for every problem listed here, and morning watering lets anything that does land dry before nightfall.
Applies to: Snow Mould (Fusarium Patch), Dollar Spot, Red Thread
Mulch the soil surface. A physical barrier between last season's spores and this season's lowest leaves removes the first infection of the year, which is the one that seeds all the others.
Applies to: Snow Mould (Fusarium Patch), Dollar Spot, Red Thread
Give the plants their full spacing 0×0 cm and keep the centre of each one open. Air moving through the planting dries the leaves faster, and leaf wetness duration is what turns a spore landing into an infection.
Applies to: Fairy Rings
Rotate this bed and everything else in the same family on at least a three-year cycle. 4 of the problems below survive in soil or crop debris between seasons, so returning the same crop to the same ground hands them the host they were waiting for.
Applies to: Snow Mould (Fusarium Patch), Dollar Spot, Fairy Rings, Red Thread
Clear and remove the spent crop at the end of the season rather than digging it in. Debris left on the surface is where the persistent problems overwinter, and next spring they start from your own bed rather than from somewhere else.
Applies to: Snow Mould (Fusarium Patch), Dollar Spot, Fairy Rings, Red Thread
Every listed problem
Ordered by how much they can cost you.
Fungal diseases(4)
- Snow Mould (Fusarium Patch)Moderate
Round patches 5–30 cm across of yellowed, then greyish-brown, matted grass. In damp mornings the edge of a patch carries white or pale pink cobwebby mycelium. Patches merge into large dead areas in a bad winter.
- How it spreads
- Rain and irrigation splash
- Compost
- Hot compost only
- Conditions
- -2–8°C · humidity ≥90% · wet leaves / rain
- First move
- Treat, then re-check in 5–7 days
- Dollar SpotMild
Small, sharply defined straw-coloured spots the size of a coin, which can merge into larger sunken areas. Individual blades carry a bleached lesion with a distinct reddish-brown border across the leaf.
- How it spreads
- Rain and irrigation splash
- Compost
- Hot compost only
- Conditions
- 15–30°C · humidity ≥85% · wet leaves / rain
- First move
- Watch it before you act
- Fairy RingsMild
A ring or arc of unusually dark green, lush grass, often with a band of dead or thin turf just inside it, and sometimes a circle of toadstools after rain. The soil under a severe ring becomes water-repellent and the grass there dies of drought.
- How it spreads
- Wind-blown spores
- Compost
- Hot compost only
- Conditions
- 12–28°C
- First move
- Watch it before you act
- Red ThreadMild
Irregular bleached or pinkish patches from 5 to 30 cm across. Close up, tiny coral-red needles or threads bind the grass blades together at the tips — the feature that gives the disease its name.
- How it spreads
- Rain and irrigation splash
- Compost
- Hot compost only
- Conditions
- 15–25°C · humidity ≥85% · wet leaves / rain
- First move
- Watch it before you act
Pests(1)
- LeatherjacketsModerate
Yellowing, thinning patches of lawn that peel back like a carpet because the roots are gone. Birds — starlings, crows, magpies — tear the turf up in numbers, which is often the first thing noticed. Grey-brown, legless, tough-skinned grubs sit in the top 5 cm of soil.
- How it spreads
- Carried by insects
- Compost
- Safe to compost
- Conditions
- 5–22°C · humidity ≥80% · wet leaves / rain
- First move
- Treat, then re-check in 5–7 days
Why rotation matters here
4 of these overwinter in the soil or in crop debris rather than on the plant. Pulling the sick plant does not remove them: they wait for the same host to come back to the same ground.