Sloe - Blackthorn
Prunus spinosa

Family: Rosaceae

What it is like

Bloom Color: White. Main Bloom Time: Mid spring. Form: Vase.

Prunus spinosa is a deciduous Shrub growing to 3 m (9ft 10in) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 4. It is in flower from March to April, and the seeds ripen in October. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very alkaline soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil. The plant can tolerate maritime exposure.

Height (m): 3

Where it is found

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

Europe, including Britain, from Scandanavia south and east to the Mediterranean, Siberia and Iran.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 3

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.

Seed: includes nuts, cereals, peas and beans.

Tea: the various herb teas that can be used in place of tea, plus the genuine article.

Medicine

Rating: 2

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. The German Commission E Monographs, a therapeutic guide to herbal medicine, approve Prunus spinosa Sloe - Blackthorn for inflammation of mouth and pharynx.

Antidiarrhoeal: Provides symptomatic relief for diarrhoea. Also see Astringent.

Antiflatulent: Reduces flatulence, particularly gas from eating legumes. See also Carminative.

Antispasmodic: Relaxes muscular spasms and cramps, calming nervous irritation.

Aperient: A mild laxative.

Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.

Depurative: Eliminates toxins and purifies the system, especially the blood.

Diaphoretic: Induces perspiration.

Diuretic: Acts on the kidneys, promoting the flow of urine.

Febrifuge: Reduces fevers.

Laxative: Stimulates bowel movements in a fairly gentle manner.

Stomachic: Aids and improves the action of the stomach.

Other

Rating: 4

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.

Cosmetic: Used to improve the physical appearence of a person.

Dye: Plants that provide dyes.

Hedge: Plants that can be grown as hedges.

Ink: Plants that can be used as an ink.

Pioneer: Plants, usually trees and shrubs, that can be used to reforest land.

Tannin: An astringent substance obtaied from plants, it is used medicinally, as a dye and mordant, stabilizer in pesticide etc.

Wood: A list of the trees and shrubs that are noted for having useful wood.

Agroforestry Services: Living fence: Simply managed rows of shrubs and trees.

Agroforestry Services: Windbreak: Linear plantings of trees and shrubs designed to enhance crop production, protect people and livestock and benefit soil and water conservation.

Industrial Crop: Oil: Materials, chemicals and energy include bioplastics, biomass, glycerin, soaps, lubricants, paints, biodiesel. Oilseed crop types.

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Regional Crop: These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.

Agroforestry Services: Living fence: Simply managed rows of shrubs and trees.

Agroforestry Services: Windbreak: Linear plantings of trees and shrubs designed to enhance crop production, protect people and livestock and benefit soil and water conservation.

Industrial Crop: Oil: Materials, chemicals and energy include bioplastics, biomass, glycerin, soaps, lubricants, paints, biodiesel. Oilseed crop types.

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Regional Crop: These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.

Attracts Wildlife: Plants noted for attracting wildlife

Carbon Farming: Plants that can be a critical part of the solution to climate problems. The Carbon Farming Solution - Eric Toensmeier.

Food Forest: Plants for Edible Forest Gardens and Food Forests.

Hedge: Hedge

How it is grown

Landscape Uses:Specimen. Requires a well-drained moisture retentive soil. Succeeds in all soils except very acid peats. Succeeds in light shade but fruits better in a sunny position. Thrives in a loamy soil, doing well on limestone. Prefers some chalk in the soil but apt to become chlorotic if too much is present. Thrives on chalk according to another report. Plants are very resistant to maritime exposure. An important food plant for the caterpillars of several species of butterfly, especially the larvae of the brown and black hairstreak butterflies. A good bee plant. Plants are shallow-rooted and of a suckering habit, they can form dense impenetrable thickets which are ideal for nesting birds, especially nightingales. Flowers are often damaged by late frosts. Plants regenerate quickly after cutting or after fast moving forest fires, producing suckers from below ground level. This species is notably resistant to honey fungus. Special Features: All or parts of this plant are poisonous, Blooms are very showy. In garden design, as well as the above-ground architecture of a plant, root structure considerations help in choosing plants that work together for their optimal soil requirements including nutrients and water. The root pattern is flat with shallow roots spreading near the soil surface. The root pattern is suckering with new plants from runners away from the plant .

Propagating it: 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.

Best place to grow: Woodland Garden Sunny Edge; Dappled Shade; Hedge;

Habit: Shrub

Hardiness: 4-8

Growth: Medium

Soil: Light (sandy), medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

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. Avoid excessive intake and use recommended doses.

Its other names

Local names

Synonyms

Prunus moldavica. Kotov. Prunus stepposa. Kotov.