Leaf Mould and the HOTBIN

Thursday, 4 September 2014  |  HOTBIN Composting

Leaf Mould and the HOTBIN

What is leaf mould?

Leaf mould is simply a pile of fully composted leaves and nothing else.

Why choose leaf mould over normal compost?

Leaf mould is a popular choice when gardeners have an excess of leaves over a short period of time, typically during the Autumn months when trees shed their leaves.

In a traditional compost heap, a large amount of leaves will slow the compost pile down and possibly stop it all together this is due to the high lignin content which bacteria find difficult to break down. A big pile of cold wet leaves will happily break down slowly over winter but in many cases will turn into a solid thick slimy layer of compressed wet leaves which will restrict aeration of the waste below and often result in the leaf part having to be turned over regularly.

To avoid this, large quantities of leaves are often separated into a leaf mould pile. This is left for 18-24 months and over time they breakdown slowly to give leaf mould compost.

How should I compost leaves in the HOTBIN?

If you have relatively small amounts you can shred these and mix them in with other waste each week, ensuring bulking agent and shredded paper are also added.

If you have a huge amount – enough to fill a HOTBIN and more, you have three choices;

  1. Store the leaves in a dry place and add a little each week.
  2. Create a traditional leaf mould heap and add leaf matter mixed with grass in the summer to the HOTBIN.
  3. Use the HOTBIN as a leaf mould bin.

Leaves and Grass

Leaves can be stored and are great to mix in with easy to digest waste such as grass. If you have a large lawn and trees mix grass and leaves 50/50 by volume, then add into HOTBIN. This mix will get to 60oC and reduce rapidly enabling you to top up in 5-7 days.

The leaf/grass combination allows the high temperature generated by the fast decomposition of the grass to help break down the leaves leaving a small amount of lignin based material in the base to finish off.

The benefits of using HOTBIN as a leaf mould bin?

Leaves like many other types of waste break down slower when cold and faster when hot.

The HOTBIN is an insulated compost bin keeping leaves warmer than a traditional heap or in a leaf mould bin. A lot of leaf decomposition is not via bacteria but via leaf litter worms (tiger worms).

To use the HOTBIN to its full potential and improve over a traditional leaf mould pile you can add in a few worms. Normally the HOTBIN’s hot composting temperatures of 40-60oC would be too hot for worms however when only adding leaves, which are slow to decompose and therefore release heat slowly the HOTBIN is unlikely to rise above 40oC and worms will thrive.