Sloes turn blue-black when ripe, usually from September, and can be found along hedgerows and fields into December. Wild Food UK suggests collecting them in October or November, preferably after they have been exposed to a frost. Picking after the first frost is traditional, but you can also pick earlier and freeze the sloes at home. Before you pick, check that the shrub really is blackthorn: this guide shows the features that tell it apart from its lookalikes.
Sloes are the fruit of blackthorn (Prunus spinosa). After pollination by insects, the flowers develop into blue-black fruits about 1 cm across. Ripe sloes can be found through the autumn months along hedgerows and fields, lasting into December.
The Woodland Trust gives the end of September to December as the time the berries are ready for picking. Wild Food UK lists a season from September to November. Climate change and weather can affect when wild foods come into season, so the Woodland Trust advises treating monthly guides as general guidance and checking what is happening locally.
It is traditional to pick sloes for gin after the first frost, but there is no reason not to pick them earlier and put them in the freezer. The theory is that frost splits the skins, so the juices can flow into the gin without you having to prick every berry. Wild Food UK says freezing them at home has the same effect.
Raw sloes will dry your mouth out in a matter of seconds, so the Woodland Trust suggests using them as a flavouring in things like vodka, whisky, jelly and syrup.
The number of sloes can vary each year according to the weather during the previous spring and summer. If it is too dry, the sloes will be small and shrivelled; if it is too wet and cold, they will not develop at all. A good crop of plump, well ripened sloes needs the right balance of warmth and water.
The fruits can also be affected by pocket plum, caused by the gall forming fungus Taphrina pruni, which leaves the developing fruits small and shrivelled.
Blackthorn is a common shrub in hedgerows. Wild Food UK looks for it around the edges of fields, grassland around woods, or poking out of hedgerows. It grows best in moist, well drained soil and thrives in full sunlight. Blackthorn is native to Europe and western Asia.
Blackthorn is spiny and densely branched, and mature plants can grow to around 4 m. The dark brown bark is smooth, and the twigs form straight side shoots that develop into thorns. The leaves are slightly wrinkled, oval, toothed, pointed at the tip and tapered at the base.
White flowers appear on short stalks before the leaves in March and April. The fruit has a pale bloom covering a dark purple to black little plum. In winter, blackthorn can be identified by its black, spiny twigs with leaf buds along the spines.
Cherry plum (Prunus cerasifera) tends to grow without thorns, flowers at the same time as the leaves emerge and has hairless twigs. Hawthorn without leaves can also be confused with blackthorn: blackthorn flowers before the leaves, and its spines have buds along their length. Wild Food UK names other plums as a possible confusion. The Forage species page for the sloe lists alder buckthorn, common buckthorn and wild privet as lookalikes.
Alder buckthorn (Frangula alnus) has a small berry that ripens from green to red and finally to dark purple or black in early autumn. Its branches and stems are smooth and thornless. Peeling back its bark reveals yellow bark underneath. Tox Info Suisse lists alder buckthorn among the plants that rarely cause severe poisoning but should not be planted on children's playgrounds because of their toxicity.
Purging buckthorn (Rhamnus cathartica) is also known as common buckthorn. It is a small, spiny tree. Its purple black berries are 6 to 10 mm across. Its leaves are opposite along the twig and have 3 to 5 pairs of curved veins that meet at the tip. Peeling back its bark reveals orange bark underneath.
Tox Info Suisse warns that black berries can be highly poisonous and that their toxicity can vary greatly. The Woodland Trust recommends checking identification tips, taking a good field guide and, better still, enlisting the help of an expert.
If you are picking sloes, the Woodland Trust says it is best to wear a thick pair of gloves. The thorns can easily penetrate the skin, break off and stay trapped, with the potential to cause infection and inflammation. Symptoms often appear days after the injury and, in rare cases, can be serious. Birds feast on the sloes in autumn.
In Germany, the Federal Nature Conservation Act allows anyone to take wild fruits in small quantities for personal use, with care, from places that are not closed to the public. Picking wild plants commercially needs a permit from the nature conservation authority.
If black berries have been eaten, Tox Info Suisse says it is imperative to identify the plant. Get medical advice immediately if you think someone may have been poisoned. Symptoms can take a few hours or days to start.
In the UK, the NHS says to call 999 or go to A&E if you think someone may have swallowed something harmful. If you are not sure whether something is harmful, call NHS 111. In the US, the poison center number is 1 800 222 1222. If the person collapses, has a seizure, has trouble breathing or cannot be woken, Poison Control says to call 911. The BVL lists the poison centres in Germany and Austria, for example the Berlin poison emergency line on 030 192 40. In Austria, the poison information centre is on +43 140 643 43. In Switzerland, Tox Info Suisse is on 145.
For other fruits and leaves you can still find later in the year, see the winter foraging guide; to see what is in season in your region right now, use the Season Finder. Both are linked below.
Branches and stems smooth and thornless. Berries ripen from green to red, then dark purple or black. Yellow bark under the surface.
A small, spiny tree. Leaves opposite, with 3 to 5 pairs of curved veins meeting at the tip. Orange bark under the surface.
Tends to grow without thorns, flowers as the leaves emerge, hairless twigs.
Dark berries in a hedge are not always sloes. Check thorns, leaves and bark before you pick, and if you are not sure, leave it. If someone has eaten berries you cannot identify, call a poison centre.
Sloes turn blue-black when ripe, usually from September, and last into December. Wild Food UK suggests collecting them in October or November, preferably after a frost.
No. Picking after the first frost is traditional, but you can pick earlier and freeze the sloes instead. The theory is that frost splits the skins so the juices flow more easily.
The Woodland Trust says raw sloes will dry your mouth out in a matter of seconds. Wild Food UK describes them as incredibly astringent.
The crop depends on the weather in the previous spring and summer. Too dry and the sloes stay small and shrivelled; too wet and cold and they do not develop at all.
Cherry plum usually has no thorns and hairless twigs. The Forage sloe page lists alder buckthorn, common buckthorn and wild privet as lookalikes. Alder buckthorn is thornless and has dark berries in early autumn. Purging buckthorn is spiny, with opposite leaves and purple black berries. Tox Info Suisse warns that black berries can be highly poisonous.
In Germany, anyone may take wild fruits in small quantities for personal use, with care, from places that are not closed to the public.
Forage shows you the species in your region and pings you when the season starts.
All information without guarantee. This text is orientation on season and habitat, not an identification guide, and it makes no claim about whether any specific plant or mushroom is edible. Many species have toxic, some deadly, lookalikes. Never eat or use anything that has not been identified with certainty by an expert, such as a qualified mushroom inspector. We accept no liability for any harm arising from the use of this information. If you suspect poisoning, call your local poison control center or emergency services right away. Mind conservation law and property rights.
