Gardeners' World star Joe Swift is urging gardeners to complete a "vital" autumn job: mulching. The garden designer says adding a layer over the soil recreates a natural blanket formed by fallen leaves and other organic material, boosting fertility and moisture retention.
Why mulch now?
The Royal Horticultural Society (RHS) explains that mulches can be loose coverings or sheets of material used to cover bare soil or compost in pots, and that they come with a range of benefits. Swift, who recently disclosed he is "ordering masses of compost" for his own garden, outlined the perks in a piece for Times Weekend.
"What's the point of mulching? After the hot, dry summer, many of us are looking to improve the moisture retention of our soil and regulate its temperature," he wrote. "Mulch also increases the fertility of soil. If deep enough, smaller 9cm plants can be planted straight into it, making life easy. I don't dig much these days as it breaks down the soil structure."
Choosing the right mulch
Swift said all types of mulch "do the job", but different kinds come with different perks. Mushroom compost is slightly alkaline, while horse manure is more acidic. He described homemade compost as "ideal", though it can be difficult to produce in sufficient quantities, and called leaf mould a "good all-rounder", while woodchips can be useful for retaining moisture.
He added that the best time of year to mulch is a debated topic for gardeners, but he tends to do it in the autumn after planting his bulbs. He advised applying mulch to a depth of around 5cm.
Where to apply and avoid
If you don't have enough to cover everything, Swift advised focusing on the roots of specific plants, but avoiding "building up against" tree trunks, shrubs, and roses, or coating the crowns of perennials.
