Grewia occidentalis

Grewia occidentalis is a South African bush that should be seen more often in gardens with mild climates or by the seaside. Vigorous and branching and as wide as it is tall, it is adorned with elegant glossy foliage that persists more or less depending on the severity of the winter and a profusion of small star-shaped flowers in a slightly mauve pink throughout the summer.  Apart from its low frost resistance (down to -6°C), Grewia occidentalis is not difficult to grow in full sun or partial shade, in any well-drained garden soil, even dry in summer. It easily integrates into a flowering hedge, can be displayed near a path, or nestled against a wall for protection, or even in a large pot on the terrace, to be stored indoors in cold regions during winter.

Grewia occidentalis (or crossberry) is classified in the family Tiliaceae, like the lime tree, or in the family Malvaceae, like Hibiscus and mallow. It is native to southern Africa, where it can be found in very diverse environments, up to Mozambique in the north and inland to Zimbabwe. It grows in the arid region of the Karoo, on coastal dunes, in evergreen forests of African mountains but also in wooded meadows, often under the cover of trees. In the wild, it can reach a height of 3m (9 ft 10 in), but in gardens with mild climates, it will usually reach a height of 1.50m (4 ft 11 in), or even 2m (6 ft 7 in) in all directions.

It has a bushy, spreading habit, carried by long flexible branches, and its growth is rather fast. It flowers for a long time, from June to August-September. The buds are covered in fuzz and grouped in small clusters in the axils of the leaves. Each flower, measuring 1.5 to 3cm (0.6 to 1.2 in) in diameter, is composed of 10 fairly narrow mauve-pink petals arranged in a staggered pattern in two rows. The centre of the corolla is occupied by a column of very bright yellow-orange stamens. The insect-pollinated flowers transform into edible fruits, with 4 lobes, ranging from shiny reddish-brown to light violet when ripe. They can persist on the tree for long periods if they escape the appetite of birds. The foliage of Grewia occidentalis is abundant and ornamental and persists during mild winters, down to -3°/-4°C. It consists of entire, ovate, rough leaves, sometimes hairy, with toothed edges, measuring 7-8cm (2.8-3.1 in) long. They are a fairly dark green colour, with a glossy appearance. This bush is capable of regrowing from the crown after short freezes of around -6°C if protected and the soil remains relatively dry. The root system of this bush is not aggressive, allowing it to be planted near the house.

Grewia occidentalis will thrive in many regions spared from severe frosts. It appreciates bright, warm exposures, and can tolerate light shade in southern regions. It can be used as a medium-sized hedge, combined with bush mallow, Phymosia umbellata, Berberis Atropurpurea for foliage contrast, Polygala, or even with a tree clover (Lespedeza thunbergii) that will accompany its flowering until the end of summer. It will also be splendid as a standalone plant or at the back of a perennial bed composed of autumn asters or shrubby salvias with blue flowers. In colder regions, it will majestically occupy a large container on the terrace or balcony during the warmer seasons and will be sheltered indoors in a bright location, protected from severe frosts over winter.

The berries of Grewia occidentalis are consumed locally, fresh or raw. After fermentation, they are used in the production of traditional beer and are mixed with goat's milk to make berry yoghurt.