Mulching not only improves the soil quality around plants and reduces the need to weed, it also helps soil retain moisture…
“Mulches are best applied from mid- to late spring and autumn, when the soil is moist and warm,” advises Mimi Rupp, a respected garden consultant and founder of Stone, etc.
“In winter and early spring the soil is too cold and our summers mean it’s too dry.”
What to choose
When it comes to mulch you have two choices:
- Biodegradable mulches (leaf mould, garden compost, wood chippings, well-rotted manure) break down gradually to release nutrients and help to improve soil structure. The downside is that mulch will need replacing when the material has fully broken down.
- Non-biodegradable mulches (slate, shingle, pebbles, gravel, stone chipping) do not boost soil quality, but they do suppress weeds, conserve moisture and some have the added advantage of looking decorative.
“Another option is permeable sheet mulches or woven landscape fabric,” adds Rupp. “They’re ideal for new beds as slits can be made to allow for planting. The downside is they don’t look very attractive, but they can be camouflaged with gravel, bark or others materials.”
How to apply mulch
According to Rupp, beds and borders can be mulched entirely, but you need to take care not to smother low growing plants or to pile mulches up against the stems of woody plants.
Here are her top mulching tips:
- To be effective, biodegradable mulches need to be between at least 5cm and ideally 7,5cm thick.
- Lay mulches over moist soil, after removing weeds, including their roots.
- Single trees and specimen shrubs are best mulched to the radius of the canopy.
- There is no need to remove mulches to apply fertilisers. Spread fertilisers over mulches in late winter so they are washed down to roots when it rains.
- A build-up of mulch can produce a hard layer, which is difficult for water to penetrate. Avoid this by only replacing a mulch when it has completely rotted away.