Colutea arborescens – Bladder Senna seed x25

Bladder Senna is not a Senna at all, though it is a member of the very large family that includes the Sennas. The common name comes from its appearance as a Senna and the balloon-like papery seed pods that persist on the plant through Autumn.

This plant comes from the Mediterranean area (Southern Europe, North Africa and Western Himalaya Mountains) where it prefers poor, sandy soils of

low nutrition value but it will survive in any soil type provided it is well drained. It was first imported to Britain in the 1500’s and has become naturalised there, then later to Eastern North America where it survives conditions of USDA zones 5 – 8 (UK zone 5) and that of Ontario, Canada.

A medium, fast growing, deciduous shrub growing 3 x 3 metres (10 x 10 ft) it has light green, pinnate leaves which colour in Autumn; yellow tinged with red pea flowers that appear for four months and an unusual paper seed pod (bladder) that persists through Autumn. The seed pods are used in floral arrangements to add interest with their bronze colouring. The leaves can be used (like Senna) as a laxative but its action takes a much milder form than Senna.

The plant can be used in landscaping, hedging, erosion control and as a feature plant in full sun to dappled shade. It has nitrogen fixing properties will tolerate drought and sandy soils but not a maritime habitat.