This is a neat small tree or good hedging plant; it is one of only two larval foodplants for the Brimstone Butterfly caterpillar. The other plant is Alder Buckthorn (Frangula alnus on acid, wet soils) It is thought that the Brimstone butterfly is common in Southern England, but scarce in North Wales simply because Purging Buckthorn (-Rhamnus cathartica, on limey or neutral soils) was not planted as farm hedging in this area. (It is NOT the same as Sea Buckthorn that is commonly used in coastal gardens)
The Brimstone is one of our few native butterflies that can fly as far as 15 miles looking for a single buckthorn in a sunny spot to lay its eggs on - so if you plant just one in your garden you will increase your chances of seeing this beautiful creature, wherever you live!
Buckthorn bark can also be used as a natural dye. Garden Tiger moth caterpillars favour this shrub as a larval foodplant.
Please specify if you would like Purging Buckthorn (for lime or neutral soils) (Natural Plant Dyers can also use the bark and berries ('Persian Berries') of these two trees)
or Alder Buckthorn (for damp, boggy and acid soils) (Dyer's Persian Berries come from this tree which readily fruits in the autumn in the UK.)
