Brilliant Buckthorn

There are supposedly only 30 odd trees and shrubs native to the UK, so it's always surprising when folk aren't familiar with one of them - or, in the case of Buckthorn, two.* 

I'm not sure why their botanical names are so different, but we have Frangula alnus, Common or Alder buckthorn (above), and Rhamnus cathartica, Purging buckthorn. They look very similar despite being apparently from different genera. Frankly, if your botanical skills are similar to mine, it's easier to tell them apart from their preferred situation. They look very similar, even including their berries, which start off red and turn black. Alder buckthorn's leaves are more rounded - supposedly like Alder - and alternate, rather than opposite. Its stems are smooth, as opposed to Purging buckthorn, which has the occasional spine - it is a Buckthorn, after all. 

Rhamnus cathartica usually grows in chalk and Frangula alnus in damp and more acidic soils. Oh, and "cathartica" as the berries are a fierce purgative - apparently widely used in the Middle Ages. "Frangula" as the buckthorn's wood is so brittle.

Although the wood's not much use, Alder buckthorn charcoal used to be valued for the gunpowder it made. Purging buckthorn had its use in times past too - as a cathartic.

Both buckthorns are often found in hedgerows but sadly rarely planted in new ones. Sadly because they're healthy looking neat plants, and super helpful for wildlife. It's odd as they're the perfect size for hedgerows too, growing to no more than 5m. I guess they're tricky to lay. This is all going to sound rather odd to American readers, incidentally, where Buckthorn is a non-native menace!

The leaves are green and glossy in spring and summer and have attractive autumn colour (photo above). Buckthorns have little yellow flowers and, like the Lonicera nitida flowers they remind me of, attract bees in particular. We sell a fair number to lepidopterists, who want to encourage Yellow Brimstones. This attractive butterfly's larvae feed exclusively on buckthorn.

We're big fans of both buckthorns, and encourage our growers to supply them. They seem to be pretty fast growing, they're tough, and relatively easy to grow from seed. It would be nice to see them more regularly specified in woodland planting schemes and included in new hedge planting. 

 

*Confusingly, neither are related to the potentially thuggish Sea-buckthorn, Hippophae rhamnoides, which is... er... not actually a buckthorn at all.