Blackthorn is one of the most abundant shrubs in British hedgerows, which landowners and farmers traditionally used to keep land borders and make cattle-proof barriers.
Sloes are the berry-like fruit of blackthorn and are the smallest and tartest of all the plum fruits. They are really appreciated and are infused in alcohol to make a flavoursome sloe gin to drink at Christmas.
Description and species
Blackthorn (Prunus spinosa) is a deciduous shrub in the plum family (Prunus), native to Europe, western Asia and northwest Africa, though naturalised in other parts of the world.
This extremely thorny shrub forms a dense thicket up to 4m and display masses of stunning white flowers in Spring, both singularly or in pairs, just before the simple oval leaves appear.
During Autumn, dark bluish grape-like fruit ripen in clusters on its branches and will remain there until around December if birds did not find them. Sloes are green-fleshed and have a little stone in the centre.
Notes on edibility
Sloes are mouth-puckeringly tart straight from the hedges but are superb after steeping in alcohol and a bit of sugar, infusing a pleasant fruity flavour rich in vitamin C. Different cultures make their own traditional drink with sloes, using different alcohol bases and spices with different results.
Spring flowers are edible and have an almond-like taste, with tonic and laxative properties. On the other hand, young leaves can be brewed into a tea to soothe throat ailments such as laryngitis and tonsillitis.
Foraging in season
Blackthorn is a widespread native shrub very common throughout the British Isles and a bit scarcer in the north of Scotland. You will find it in hedgerows and scrubland, woodland edges and parks, often growing in poor soil.
Its white flowers are fairly easy to spot in early Spring, as it’s one of the earliest blooms of the year. Sloes on the other hand, are traditionally picked between September (in very early seasons) to November, preferably after the first frost, which will soften the acidity of their flesh.
Sloes are naturally tart, so the longer you can leave the berries on the tree the better. The fruit remains attached to the shrub for a prolonged period, long after the leaves have fallen, occasionally persisting until Christmas.
Sloes form in huge quantities around the branches and would be fairly easy to pick them if it weren’t for those sharp thorns watching over the fruit; in fact it is advisable to wear gardening gloves and be extremely careful.
Storage and processing
Traditionally, sloes used to be harvested just after the first frost, as it would soften the skin to help release the juices and allow alcohol permeate the fruit. Fortunately, we’ve got freezers today, which will replicate the frost effect.
Flowers are best picked when they are still a little bit closed. Afterwards they need to be dried in a well ventilated and dark place to avoid discoloration and mould.
Culinary uses and recipes
Sloes are rather tart and astringent when eaten raw; although cooking releases the sugars in the fruit making them more palatable, they are most suitable for preserving and generally shine in alcohol infusions and liqueurs.
Sloe gin is the first thought that comes to most foragers’ minds. It’s not a true gin, but an infusion of gin with the fruit and sugar to produce a fine liqueur with both sweet and tangy flavour that turns deep red after a long period of maturation.
Three to six months is considered the optimum maturation time to achieve a satisfactory result. The longer you leave the sloes to infuse, the deeper the alcohol will penetrate. After one year, the almond-like flavour coming from the stone starts to become noticeable.
Many European countries have a traditional liqueur made of sloes; for instance, patxaran is quite popular in Spain, which is made of the fruit infused in anisette along with a few coffee beans and a bit of cinnamon, producing a very refreshing drink.
Italians make bargnolino infusing sloes in grappa meanwhile Germans infuse them in white rum to produce Schlehenlikör. A different approach in France develops troussepinette or vin d’épines, which uses the young spring shoots infused in eau de vie to produce an aperitif.
You can find plenty of variations with vodka, whisky, brandy and vermouth on internet. Even sloe leftovers can be used to make slider, a still cider in which the sloes used to make sloe gin have been steeped.
These fruit leftovers have been traditionally used to make sloe gin chocolates in Britain, but you can also add the fruit to cakes or make sloe jelly, fruit leather or fruit cheese. It imparts a pleasant warming zing to any sweet recipe.
Blackthorn flowers are also edible and taste a bit like almonds. Try adding them to alcohol infusions; freeze them into ice cubes or use them as a cake decoration.
Now, what’s your favourite boozy recipe?