BlackthornFiona Chan-Cary, CC BY 4.0
Native · Up to 6 m

Blackthorn

Prunus spinosa · Rosaceae

Also called sloe

Blackthorn is a dense shrub with stiff, thorny branches. Its white flowers open on the bare, almost black stems in March, and in autumn it carries dusty blue sloes.

Often mistaken for hawthorn. How to tell them apart →
Know it byLeavesSmall plain ovals, dull and slightly wrinkled.BlossomWhite blossom on bare wood, in March.SloesSmall, round, dusty blue sloes from September.

Then check · ThornsMany side-shoots end in a sharp thorn, with tiny buds along the thorn itself.

How to identify a blackthorn

Blackthorn: leaves
Leaves

Blackthorn leaves are small, plain ovals, widest at or above the middle, with fine teeth round the edge. They are dull green and slightly wrinkled.

Blackthorn: blossomFiona Chan-Cary, CC BY 4.0
Blossom

In March the whole bush turns white before a single leaf is out. Close to, the small five-petalled flowers sit singly or in pairs on bare, dark, thorny stems.

Blackthorn: sloesAndy Jordan, CC BY 4.0
Sloes

From September, small round sloes hang along the stems, blue under a dusty bloom. The bloom rubs off to show black skin, and some sloes stay on into winter.

Learn the blackthorn in TreelyEvery part through the year, and a short round each day until you know it.Get Treely

Every part, in photographs

Blackthorn leaves: small and wrinkled, widest at or above the middle
LeavesSmall and wrinkled, widest at or above the middle
Blackthorn blossom: off-white, five petals, out before the leaves
BlossomOff-white, five petals, out before the leaves
Blackthorn sloes: dusty blue sloes, black under the bloomNicola Crockford, CC BY 4.0
SloesDusty blue sloes, black under the bloom
Blackthorn thorns and buds: purple shoots, tiny buds set on the spinesDaniel Cahen, CC BY 4.0
Thorns and budsPurple shoots, tiny buds set on the spines
Blackthorn thicket: dense thorny thicket, spreading from the rootsFiona Chan-Cary, CC BY 4.0
ThicketDense thorny thicket, spreading from the roots

When to look

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In leaf
Flowers
Sloes

In leaf: March to November · Flowers: March to April · Sloes: June to December

Every tree on the calendar · How to identify trees in winter

Where you’ll find it

Hedgerows, scrub, woodland edges, chalk downland and scrub by the sea. On heavier soils it is often the main shrub in hedges. Common throughout Britain and Ireland.

What it’s mistaken for

Blackthorn: flowers and leaves, and whenHawthorn: flowers and leaves, and whenBlackthorn or hawthorn?Both are thorny hedgerow shrubs with white flowers.Flowers and leaves, and when Blackthorn: flower and its stalkCherry plum: flower and its stalkBlackthorn or cherry plum?Also white-flowered in early spring.Flower and its stalk Blackthorn: top of a leafSpindle: top of a leafBlackthorn or spindle?Its leaves are much the shape of a blackthorn leaf, and the two share a hedge.Top of a leaf Blackthorn: whole plantWild cherry: whole plantBlackthorn or wild cherry?White spring blossom at the edges of the same woods.Whole plant

More cherries, hawthorns, rowans and apples

AppleMalus domesticaCherry laurelPrunus laurocerasusCherry plumPrunus cerasiferaCommon whitebeamSorbus ariaCrab appleMalus sylvestrisHawthornCrataegus monogynaMidland hawthornCrataegus laevigataOrnamental cherryPrunus serrulata and its garden kin
In the app

There’s more of the blackthorn in Treely

  • Every part, through the yearLeaves, bark, buds, flowers and fruit, photographed in every season
  • Its lookalikes, side by sideThe checks that settle it, part by part
  • A short round each dayUntil you know the blackthorn on sight, from any side
  • Name it from a photoA leaf, the bark or a flower, and Treely tells you which tree
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Every fact on this page is checked against the Collins Tree Guide, last in November 2026. Spotted something that looks wrong in front of a real tree? Tell us. How we check.

Photographs: Fiona Chan-Cary (CC BY 4.0), steve_mcwilliam (CC0), Andy Jordan (CC BY 4.0), empressmoth (CC0), Nicola Crockford (CC BY 4.0), Daniel Cahen (CC BY 4.0), cjoynson (CC0), Virn Stothers (CC BY 4.0), jsilloth (CC0), jamie-aa (CC BY 4.0). With thanks to everyone who shares their photographs on iNaturalist and Wikimedia Commons.