Compost topdressing in autumn
A thin layer of fine compost once a year, best right after autumn aeration, builds soil life, improves drainage and feeds the grass slowly.
- When
- Sep 20 – Oct 31 (northern hemisphere) · Mar 20 – Apr 30 (southern)
- For
- Any lawn
- Rule
- au-topdress · Hessayon; RHS; Regional
A thin layer of fine compost once a year — best right after autumn aeration — builds soil life, improves drainage and feeds the grass slowly. A cheap, organic way to build the soil.
What it does
Fine compost brushed into the lawn adds organic matter to the top of the soil, where most grass roots are. Over seasons it improves structure, so clay drains better and sand holds more water, feeds soil life that breaks down thatch, and releases nutrients slowly. It also evens out small dips.
When
Late September to the end of October, ideally straight after aeration and overseeding, so the material drops into the holes and covers the seed.
How much
About 0.5–1 cm (¼–⅜ in) at most, roughly 5–10 liters per m² (1–2 cubic feet per 100 sq ft). The grass blades must still show through when you finish.
How
- Use fine, well-rotted, screened compost, or a compost-and-sand mix on heavy soil.
- Tip small piles across the lawn and spread with the back of a rake.
- Work it in with a stiff brush or drag mat until it disappears into the sward.
- Water lightly if no rain is due.
Sources
- D.G. Hessayon — The Lawn Experthessayon
- Royal Horticultural Society — lawn guidancerhs
- Regional practice — continental climate, zone 7regional