How To Make Leafmould

Make Leafmould Yourself

We keep harping on about things like garden hygiene. After a day such as this spent raking up leaves blown off our hedging by the unseasonably high winds last week, we try another tack and suggest a leaf rake, a still autumnal day and a few calories worth of energy expended as being all that is required to clear up this season's leaf fall. 

There are many good reasons for doing this but the best is that you can make your own crumbly, rich leaf mould that (apart from some good exercise) will improve, transform and mulch your beds in coming years... for free.

Trees like beech, oak and hornbeam produce smaller, thinner leaves which are the créme de la créme when it comes to making leaf mould because they rot down more quickly than, for instance, horse chestnut or sycamore trees.

Of course, if you have the patience you can shred the latter before adding them to your leaf heap - or just be prepared to wait a bit longer for them to decay. The larger leaves are not bad - they just need more time.

If you don't have masses of leaves, the simplest thing is to pack them quite tightly into black bin bags. Just make sure that the leaves are damp - pretty likely anyway, but wet them if they are dry. Tie up the mouth of the bag and then stick the tines of a fork into the bag a couple of times to allow some air to circulate. Tuck the bags away somewhere out of sight for a couple of years at the end of which you will have the most brilliant leafmould - so like crumble mix that you can use it as is for seed sowing or as an ingredient in homemade potting compost.

Impatient and can't wait two years? Well, leave them for a measly 12 months and they will have broken down to the point where you have a fabulous soil conditioner or autumn mulch for your bed, hedges and trees.

Gardeners whose leaf output is too much for a few black bags should build a leafmould container. Use four or six tall stakes depending on whether your feng shui demands something rectangular or square. Make a wall out of chicken wire tied to the posts (use wire as it lasts longer than string, and keep the posts outside the wire. It is tempting to wrap the wire around the outside of the corner posts, but if you keep it inside, then the posts support the weight of the leafmould rather than the netting tearing away from the posts.

Site the container somewhere out of the way - and leave room for another as you usually fill one while another rots down.

Line the bottom with a bit of Permatex or similar so weeds do not grow up and through your leafmould. In one of those scorching summers we see with such regularity, moisten the pile occasionally to speed decomposition.

Not all leaves are equal

Most leaves are fine to add to your pile, but there are few that are not:

1. No evergreen leaves (holly, laurel, conifers etc)

These are best consigned to the compost heap where they rot more efficiently. If you have lots of pine needles shed in spring, pile them up and keep them for two years to make an acidic leafmould for any ericaceous plants like rhododendrons or azaleas.

2. No fruit tree leaves

Orchard leaves from apple, cherry and pear trees are best disposed of by bagging them up and taking them to a green waste recycling plant or burning them. Scab, its close cousins and a range of rusts, leaf spots, blights and other fungal diseases are just too common an affliction on fruit trees to risk composting leaves that may well be infected.

Almost all fungal diseases that attack leaves have a life cycle where their spores overwinter in leaf litter beneath the infected tree. With spring and warmer days, rising air currents help the spores back into the tree to re-infect it. As a spore can survive for years until conditions are right, a leaf-heap would provide ideal overwintering conditions.

3. No rose leaves

Roses belong to the same family as many fruit trees, suffer from closely related diseases and so their leaves should be destroyed as well.

Other Benefits of Leafmould

Removing leaves from lawns and beds deprives slugs and snails of nice hidey places to pass the winter months. Dealing with the leaves is a way of preventing infestations of these, the bane of all gardeners, and reduces your spend on slug pellets - an all their nasty chemicals - next year.

Leaves left to rot on paths make them slippery and over the years will accelerate your need to repair them.

Leaves left on lawns will ruin the grass beneath them.

So enough of the jaw-jaw.....off with you and your rake, smartly into the garden.