Most leaves can be turned into leaf mould, but some varieties take longer to compost than others.
It is advisable not to use evergreen leaves, and pine needles.
Subject to the type of leaves used, it can take up to two year for the leaves to fully decompose.
Material less than two years old is suitable for use as mulch and or a soil improver.
Fully matured leafmould can be used as a seed-sowing mix or as potting compost when mixed in equal parts with sharp sand and garden compost.
Typical leaf mould
Collect leaves in autumn, and put them in a plastic bag e.g. a bin liner.
Don't disturb drifts of autumn leaves under hedges and other out of the way areas,as these maybe being used as hibernating sites by hedgehogs and other creatures.
If the leaves are dry give them a good soaking, pierce the bag a number of times, tie the top loosely and then place them somewhere out of the way until they have rotted down.
Alternatively erect a four sided or round cage with chicken wire or mesh fixed to posts that have been driven into the ground, and place the leaves in this.