Are pine needles the friend or foe of gardeners?
All leaves are our friends, because they break down to make leaf mould. This is magic stuff that can be used as seed compost, or as a mulch for woodland plants, or added to any soil to increase moisture and improve root growth by boosting fungal activity.
Some leaves take longer than others to break down. The quickest leaf mould tends to be from beech, hornbeam or oak. Pine needles are not quick to rot down, but when they do, they are acidic, making perfect leaf mould for ericaceous plants such as blueberries, rhododendrons, azaleas, camellias, heathers and pieris.
Conifer needles are less exciting, because they take such a long time to rot (two to three years) and aren’t as acidic. Evergreens such as holly, aucuba and cherry laurel are also a bit of a pain: I think these are best shredded before adding to the leaf mould pile, because this will help them break down faster.
Aim to keep deciduous leaves in a separate pile from evergreens, because evergreens take so much longer to break down. Once they have, they make a great leaf mould.
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