Mulch is a layer of material placed over the soil and around plants. It has a number of practical benefits, not to mention that it makes your garden look really smart! It can help to suppress weeds as well as lock moisture into the soil. If an organic mulch is used, this will also feed the soil and improve the soil’s structure as it breaks down.
To mulch correctly, spread 2 – 3 inches of mulch evenly around your plants. If mulching a tree, create a circle at least 1m in diameter and make sure that no mulch is touching the trunk itself. With larger trees, ideally mulch to the drip line of the tree to get the maximum benefits.
When mulching a border, spread the mulch throughout, ensuring you don’t smother any perennials and as with trees, keep the mulch away from the stems of any woody plants.
Types of mulch:
- Garden compost
- Bark chippings, shredded bark, wood chippings and wood shavings
- Leaf mould
- Well-rotted horse manure (ensure it has been left to rot for at least two years before use)
- Coconut husk chips
- Small rocks or gravel
When to mulch
From mid- to late spring (when herbaceous plants are dormant) and in autumn, as plants are dying back. New plants that need to establish can be mulched at any time of the year.
BEWARE the mulch volcano!
Also known as a mulch mound, it is when too much mulch is piled up around the base of a tree or shrub. It is detrimental to the health of the plant and can cause the following issues:
- Bark damage
- Root dehydration
- Root girdling (a root that grows in a circular or spiral pattern around the trunk or at or below the soil line, gradually strangling the trunk)
- Tree stress
The tree isn’t killed immediately; the harmful effects are much more insidious.