Euphorbias are a varied genus of plants that include cacti-like succulents and the leathery-leaved wood spurges that we are more familiar with from our gardens. Most species produce tiny flowers surrounded by long-lasting, conspicuous bracts. These appear in various colours - red, purple, yellow and the glorious acid-green that we most associate with euphorbias. In autumn the foliage of many species, particularly some Chinese ones, turns brilliant red, orange, purple and yellow.

Euphorbia amygdaloides var. robbiae Mrs Robb's bonnet has broader, darker, tougher leaves than the species.