leaf on groundFifty plus years ago, I used to help my dad in our Market Garden/Plant nursery. We used to grow a wide range of flowers and vegetables. I remember each Autumn in the late 60’s, my Dad would ask a neighbour (a man who drove the local council vacuum sweeper waggon) if he could empty its contents of leaves in a pile at the corner of our nursery, instead of putting them on the local tip. Dad even chose certain roads where he knew the trees and that there would be just leaves, very little traffic and not rubbish! When we had a good quantity of leaves we would leave them to rot and then spread them on the land as good humus. We also used horse manure with straw from the local stables.

Later in life, I read the book, ‘Grow your own fruit and vegetables’ by Lawrence D. Hills. Hills was a pioneer in organic gardening and started the Henry Doubleday Research Association (later to become Garden Organic). I was especially interested in the chapter ‘Muck without Magic’ Here he explained the use of leaf mould and suggested speaking to the local Borough Engineer about collecting leaves. However, this book was published in 1971 when roads were far less polluted or busy with traffic.

Today, for many reasons I, and a lot of organic gardeners, value leaf mould as a cheaper and more environmentally friendly replacement for peat. Peat is one of the best natural materials to store carbon.. We need to capture and keep carbon underground so should preserve this valuable resource. However, leaf mould is a good replacement.

How can we make leaf mould today?

First collect your leaves! Beech leaves are particularly good, although any deciduous tree leaves are fine. This is usually in October/November and can be from your garden or someone you know with an excess of fallen leaves. Lawrence Hills warns of the dangers of burning leaves as rubbish, not just to the planet but the smoke can also be carcinogenic. We need to be wary of collecting street leaves too these days, as they can contain pollutants from vehicles plus rubbish that you don’t want.

Next, to produce leaf mould for use in the garden, find something to collect your leaves in (Not plastic bin bags as they perish).
Because we have a lot of leaves, we use builders bags which seem to work OK. You could make a box or cage with chicken netting if you wish. Whatever you use, the leaves need air and to be roughly enclosed to stop them blowing away. Pack them in but not too tightly.

leaf mould samples

Finally, don’t let them dry out too much in the summer and within 12 months they can be suitable for digging in the garden. If you leave them a year longer they will turn into a really good peat substitute with a finer texture.

Paul Butterworth

Editor’ note: Like pure peat, leaf mould is low in nutrients, as trees draw these back into their own structures before shedding their leaves. Commercial peat-based composts usually have added nutrients, so you too need to add nutrients, for example in homemade compost, if using leaf mould as a potting compost or seed compost for small seeds. This is less important if it’s being used as a seed compost for large vegetable seeds, such as peas and beans, as they have their own stored nutrients to get them started but will need transplanting before these are depleted.