Herb: Sloe

Latin name: Prunus spinosa

Family: Rosaceae (Rose Family)

Medicinal use of Sloe:

The flowers, bark, leaves and fruits are aperient, astringent, depurative, diaphoretic, diuretic, febrifuge, laxative and stomachic. An infusion of the flowers is used in the treatment of diarrhoea (especially for children), bladder and kidney disorders, stomach weakness et. Although no specific mention has been seen for this species, all members of the genus contain amygdalin and prunasin, substances which break down in water to form hydrocyanic acid (cyanide or prussic acid). In small amounts this exceedingly poisonous compound stimulates respiration, improves digestion and gives a sense of well-being.

Description of the plant:


3 m
(9 3/4 foot)

to April

Habitat of the herb:

Hedgerows and woods, usually in sunny positions, on all soils except acid peats.

Edible parts of Sloe:

Fruit - raw or cooked. Exceedingly astringent, it is normally cooked but once the fruit has been frosted it loses some of its astringency and some people find they can enjoy it raw. The fruit is more usually used in jellies, syrups, conserves etc and as a flavouring for sloe gin and other liqueurs. Some fruits that we ate in December were fairly pleasant raw. In France the unripe fruit is pickled like an olive. The fruit is about 15mm in diameter and contains one large seed. Seed - raw or cooked. Do not eat the seed if it is too bitter - see the notes above on toxicity. The leaves are used as a tea substitute. The dried fruits can be added to herbal teas. The flowers are edible and can be crystallised or sugared.

Other uses of the herb:

The bark is a good source of tannin. It is used to make an ink. The juice of unripe fruits is used as a laundry mark, it is almost indelible. The pulped ripe fruit is used cosmetically in making astringent face-masks. A green dye can be obtained from the leaves. A dark grey to green dye can be obtained from the fruit. The bark, boiled in an alkali, produces a yellow dye. The sloe is very resistant to maritime exposure and also suckers freely. It can be used as a hedge in exposed maritime positions. The hedge is stock-proof if it is well maintained, though it is rather bare in the winter and, unless the hedge is rather wide, it is not a very good shelter at this time. Because of its suckering habit, the plant is a natural pioneer species, invading cultivated fields and creating conditions conducive to the regeneration of woodland. Wood - very hard. Used for turnery, the teeth of rakes etc. Suitable branches are used for making walking sticks and are highly valued for this purpose because of their twisted and interesting shapes.

Propagation of Sloe:

Seed - requires 2 - 3 months cold stratification and is best sown in a cold frame as soon as it is ripe. Sow stored seed in a cold frame as early in the year as possible. Protect the seed from mice etc. The seed can be rather slow, sometimes taking 18 months to germinate. Prick out the seedlings into individual pots when they are large enough to handle. Grow them on in a greenhouse or cold frame for their first winter and plant them out in late spring or early summer of the following year. Cuttings of half-ripe wood with a heel, July/August in a frame. Softwood cuttings from strongly growing plants in spring to early summer in a frame. Layering in spring. Division of suckers during the dormant season. They can be planted out direct into their permanent positions.

Cultivation of the herb:

Hedgerows and woods, usually in sunny positions, on all soils except acid peats.

Known hazards of Prunus spinosa:

Although no specific mention has been seen for this species, it belongs to a genus where most, if not all members of the genus produce hydrogen cyanide, a poison that gives almonds their characteristic flavour. This toxin is found mainly in the leaves and seed and is readily detected by its bitter taste. It is usually present in too small a quantity to do any harm but any very bitter seed or fruit should not be eaten. In small quantities, hydrogen cyanide has been shown to stimulate respiration and improve digestion, it is also claimed to be of benefit in the treatment of cancer. In excess, however, it can cause respiratory failure and even death.

Plant information taken from the Plants For A Future.