The last fruit of the British autumn, sloes are the small, plum-like fruits of the blackthorn tree, which is often used in hedging. A wild ancestor of modern cultivated plums, sloes' bluish-black colour is similar to that of black grapes, and like plums they have a soft bloom on their skins.
Although sloes appear in hedges around August, they are traditionally not picked until after the first few frosts, late in October or November, because then the flavour is sweeter and the skins softer.
IN THE KITCHEN
Sloes are much too sharp to eat raw, and they have limited uses when cooked. Their high pectin content means that they are sometimes combined with other fruit in jams and jellies to encourage the preserve to set. More common, however, is to use them to flavour gin. The sloes are combined with sugar and alcohol and left to steep in a cool, dark place for several months, before being strained and rebottled. A similar method is used to make sloe flavoured vinegar. They can also be used to make fruit wine.
When preparing sloes for steeping, they can either be pricked all over with a needle, or put in the freezer for a couple of days so that the skins split.