Senna corymbosa “John Ball” – Buttercup Bush
Racemes of bright yellow flowers, the colour and texture of buttercup petals, from autumn through winter.
This plant forms a rounded bush up to 4M tall with a relatively open habit. It is a member of the pea family (Fabaceae) and has evergreen, pinnate leaves and interesting pendulous seed pods. The flowers are a magnet for nectar drinking insects during winter. This is a vigorous plant, so do give it enough space.
S. corymbosa comes from South America, and is sometimes known as Argentine Senna. It is the source of one of the most famous of all herbal remedies, Senokot, which is widely available today as a laxative. C. corymbosa is actually a cross between Senna multi-glandulosa and Senna septentrionalis. The variety shown here would normally be referred to Cassia “John Ball” in New Zealand.
Soil / Aspect:
This plant is not fully hardy but is completely fine through the winters in Karin’s garden. It does well in the slightly acid soils in Karin’s Garden. Indeed it is supposed to prefer a loamy or peaty soil but does not seem to mind the clay found around Motueka, where there are several fine specimens.
S. corymbosa responds well to pruning, usually producing a new flush of flowers on the new growth. It can be pruned/trained flat against a fence, but it is really too vigorous to be used as a hedge.