Sheet mulch (advanced)

Sheet mulching involves covering weed-infested ground with a thich layer of different mulching material to starve weeds of light.

Sheet mulches need to be left for at least a year, and perhaps up to 3 years, to kill or weaken persistent weeds.

Clear the area of any large debris. Then cover with large cardboard sheets which overlap or use old, natural carpet (with no rubber) which will breakdown over time. In smaller areas, use thick layers of newspaper.

Hold this layer down with 10 cm (4 in) garden compost, rotted manure, top soil or leafmould. As an optional finish, cover with a layer of straw or grass cuttings to keep neat and moist.

As the mulch settles, weeds underneath are starved of sunlight, die and rot. The cardboard or natural carpet will break down over time.

The ground will be free of annual weeds, and perennial weeds will be weakened. Perennial weeds may break the sheet mulch and should be removed. Remove any remnants of these perennial weeds.