How is leaf mould different?
Leaf mulch and leaf mould are often confused by many, as leaf mulch eventually breaks down into leaf mould. Leaf mould is a thick, black crumbly substance that acts as a soil conditioner which helps the soil structure and helps it retain moisture.
Is leaf mulch acidic?
Most leaves are slightly acidic when they fall, as leaves break down they return to a natural pH. Some leaves aren’t suitable for mulch at all. Some contain natural herbicides that can inhibit plant growth. Camphor, walnut and eucalyptus are notorious for this effect and strongly advised against use for mulch, mould or compost.
What about evergreen leaves?
Evergreen leaves like holly, forsythia and cheery laurel should be added to your leaf mould pile instead as these take longer to break down. Likewise, conifer needles can take years to break down, these should be added to your compost where microbes and decomposers are more plentiful.
How does it compare to bark mulch?
Outside of making your own, leaf mulch can be expensive. Bark mulch is an inexpensive and accessible mulch alternative for many, it’s frequently used in landscaping and is very decorative. It’s a great way to recycle unwanted manufacture waste. It’s excellent for insulating roots and retaining moisture, as they eventually decompose, they return nutrients and a lot of nitrogen to the soil.
Be careful not to turn into your soil as it doesn’t mix as efficiently as softer mulches, like those made of leaves. Be wary too, bark can be dyed, and some of that residual dye is inorganic. So, if you’re looking for a wholly organic approach, look out for additives and synthetic dyes.
How long does leaf mulch last for?
A good covering of leaf mulch will last for up to a year, by which time your 3 or so inches you started with will now be less than one inch. Keep an eye on this, and when it’s low, turn that last part of decaying mulch into the topsoil and then replenish with a new layer of mulch 3-4 inches thick.