The genus Avonia, which is sometimes included in the genus Anacampseros, occurs mainly in South Africa with a few outliers in Namibia, Zimbabwe and Somalia. Most of them have relatively small flowers with the exception of Avonia quinaria, which has large showy flowers that appear in mid-summer. They open in mid-afternoon and are still open for you to see on returning from work in the evening.
There are two subspecies which differ only in the colour and size of flowers. Subspecies A quinariais the purple-flowered southern element that can be found from near Springbok airport to Kliprand in the Northern Cape Province of South Africa (Fig 1).
Subspecies A alstonii grows north of this in a band from near Steinkopf east to Pofadder and it produces larger pinkish-white flowers (Fig 2). They are still widespread and plentiful in the wild in spite of earlier illegal collecting and can be found growing in flat quartz-strewn areas or quartz crevices, either on the plains or on plateau areas of hills.
The main water-storage part of the species is a fat base or caudex that can reach about 12cm diameter in
very old specimens. The top of this has many growing points that produce narrow stems covered with silvery scales; the flowers being terminal on the very ends of these. Unfortunately it is very slow-growing and it takes me about four years to produce a plant from seed that has a 1cm diameter caudex. However, I find it surprising that it will start to flower at about two years old, when the caudex is just a few millimetres across. The species is susceptible to overwatering and I therefore use a very open compost consisting of 1 part each of John Innes compost No.2 and 4mm grit. It should be treated as a summer-grower and watered from March to October. Grow in full sun and keep frost-free and dry during winter.
Most Avonias are self-fertile and produce copious quantities of seed without any help. Avonia quinaria is one of the few exceptions in that it is self-sterile and hand pollination between two individuals is needed. Seed capsules ripen within a few weeks and the seed is easily lost if they are not closely watched. The seed does not remain viable for very long but can be kept for sowing on the surface of seed compost in gentle heat in the following spring.