British Native Trees
and Shrubs

Buckthorn Rhamnus cathartica (Rhamnaceae)

Buckthorn usually makes a bushy deciduous shrub about 5 m tall with thick foliage growing from near the ground, but it can sometimes be a tree reaching twice that height. The rough bark is grey-brown, almost black on the young twigs, and the shoots are of two kinds: longer growth shoots and short leaf and flower shoots. The latter grow opposite one another, almost at right angles to the stem, and often end in a stout spine. From April they carry dull green, finely toothed, rounded ovate leaves, up to 7 cm long, with three or four pairs of lateral veins curving towards the tip. They turn brownish-yellow in autumn. Inconspicuous clusters of tiny, four-petalled, yellowish-green flowers appear at the base of the leaf stalk in spring, male and female on separate plants. From September the female plant carries an abundant crop of pea-sized, three or four-seed fruits, green at first but ripening to shiny black and often remaining on the bush after leaf fall.

Buckthorn occurs in woods, scrub and hedgerows on calcareous soils mainly in the south, east and midlands of England, but also found as far north as the Lake District and the Tees.

It can be grown as a free-standing tree or as a hedge, but to be sure of the decorative autumn berries one male must be planted to every five or six females. The berries are purgative but not very poisonous. Buckthorn is generally a problem-free plant well suited to small wildlife gardens, paticularly in towns. It grows in sun or semi-shade and is fairly tolerant of most soils, although it prefers free-draining, alkaline soil, making it a useful shrub for a dry, chalky garden. It is easily propagated from fruits gathered in autumn, stratified until February and sown in nursery beds. Line out in autumn and grow on for up to two years before planting out permanently. To be sure of the sex , it is better to take semi-hardwood cuttings with a heel in late summer, or the plant can be layered in spring.

Buckthorn is the main foodplant of the brimstone butterfly, but the larvae of the green hairstreak also feed on it. The leaves can also attract crown rust which appears as orange specks and as this attacks cereals it is best not to plant buckthorn near arable land. The berries are a valuable food for wintering birds.

Page last updated - January 10, 2002  

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