Biennial herb to over 0.5 m tall. Stems red at the base. Leaf stalks red, leaf blades deeply divided. Flowers pinkish purple, with the veins paler at the base.
The impression of this plant is of a giant G. robertianum. It is closely related to G. canariense from the Canary Islands and G. maderense from Madeira, both of which are available in nurseries. Important differences between these species are indicated in the key.
Care is needed with these species as they have shown the potential to become weedy. G. rubescens has naturalised in a few suburbs of Melbourne.
Source: (2002). Geraniaceae. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.