Growing the river indigo shrub

This graceful shrub or small tree attains a height of up to 4m and has small, sweetly scented flowers that are pink and white in colour.

Indigofera jucunda, the river indigo shrub, used to be called I. cylindrica. Confusion still occurs with the name, and the plant is sometimes incorrectly labelled in nurseries and botanical gardens.

Indigofera is a large genus of more than 800 species of mostly herbs and undershrubs. The genus name means 'bearing indigo'. Indigo is one of the oldest known colouring agents. I. tinctoria, a species originally from the Malay Archipelago, yields the dye 'indigo'.

A SOUTH AFRICAN PLANT

The species name jucunda means 'pleasing'. The misapplied name cylindrica means 'cylindrical' and refers to the shape of the seed pods.

I. jucunda grows wild in the Eastern Cape and southern coastal areas of KwaZulu-Natal, where it occurs in bushveld, riverine forest and on sandstone outcrops. It prefers to grow on rocky outcrops and hill slopes, often with other trees.

A small, hardy, evergreen tree, it grows about 3m high and has sprays of showy flowers that bloom for an exceptionally long time in summer. The main stem is greyish brown, and the leaves are dark green and up to 10cm long. Leaflets are ovate to elliptical and occur in pairs.

The flowers are small, a mauve/pinkand-white colour and pea-shaped. They are borne in profusion on short racemes of up to 5cm long during summer, from December through to April.