Mushrooms keep returning to the lawn: what could reduce them?

These look like shaggy inkcaps. The mushrooms you see are only fruiting bodies; the fungus itself is already in the soil, feeding on old organic material, often dead roots, thatch or buried wood. Removing the caps therefore helps only temporarily, but is still worthwhile to limit new spores and tidy the lawn now.

What you can do now

• Pick up the mushrooms as soon as they appear, ideally before they blacken and dissolve.
• Rake lightly where they appear and remove loose organic debris, old grass clippings and thick thatch.
• Water less often if you normally irrigate the lawn. In September, natural rainfall often goes a long way on an established lawn.
• Aerate the worst patches with a garden fork or aerator if the ground feels compacted and remains wet long after rain.

For a longer-term reduction, make the conditions less favourable: better drainage, less accumulated organic material and a denser, stronger lawn. If mushrooms repeatedly appear in exactly the same spot, there is often something underground, such as old roots or wood, and they will not disappear completely until it decomposes. Chemical treatments rarely have a useful, lasting effect in lawns. Once growth slows this autumn, scarify or rake out thatch from thick, damp areas, then aerate the same ground.