Fall the time to start making Leafmould

While leaves can be composted at anytime, and green summer leaves usually are, large quantities of leaves resulting from the autumn fall presents a challenge calling for the use of  different techniques and over the next few blogs I will cinsider some of them.

Even a cool compost bin will generates heat, in part, due to the activity of bacteria  breaking down its contents. The process of producing leafmould generally relies on fungal action rather than bacterial activity and occurs at lower temperatures so that while compost takes a few weeks, or months depending on the process being used , leafmould usually takes a year or two.

  The autumn leaves are an excellent source of carbon but are very slow to compost using conventional techniques.  Leaves can take a long time to compost. They are “Browns” being high in carbon, with a C/N ratio averaging at about 60 but ranging from 20-100. So if they are to be composted they will need to be accompanied by a good source of nitrogen to keep the balance in the bin.  The amount of lignin, calcium and nitrogen in the leaves will also affect the time it takes for them to breakdown. In general as leaves take a long time to compost and have a tendency to mat, this may result in anaerobic fermentation. 

 Leafmould can be used as  a mulch, soil conditioner, in a potting mix or seed compost. It has an earthy, dark brown texture and the smell will remind you of a woodland floor in spring or early summer. It is excellent at water retention and improving soil structure.

It can be used after a  year, when the leaves are beginning to break down and the material is  easily crumbled, as a soil improver or  mulch around shrubs, and in ther flower or  vegetable garden.  It can also be used as a lawn top dressing in the Autumn.

However it is best  kept for two years  or more until it is  dark brown in colour,  crumbly  with no real trace of original leaves visible. At this stage it can be used to make a compost suitable for sowing seeds  mixed with equal parts sharp sand and garden compost or to make a  Potting compost using  equal parts well rotted leafmould, sharp sand, loam and garden compost. See the my page on these at www. carryoncompsting.com   Compost Mixes

It is also a good idea to  bag and save some dry shredded leaves  for use as a source of browns when composting during the winter when there is less garden waste available and the main addition to the compost bin is kitchen food waste.

In the next leafmould blog I will start looking at different techniques. This blog is taken from the leafmould page at www.carryoncomposting.com