Ardisia crispa: Coral Berry
Unlike the preceding plant, the one in this illustration belongs to the traditional group of house plants which indicates that it needs fairly cool conditions in winter. However, since the required temperature is approximately 15°C (59°F), which is more or less the average temperature of house corridors and other circulation areas such as glassed-in foyers, it would surely be a pity to bypass this delightful little shrub.
Ardisia crispa is native to China where it grows at the edge of subtropical forests that dry out periodically or in similar open situations. According to some .authorities its range extends as far as Indo-Malaysia. Ardisia is a fairly large genus; its 250 or so species are distributed in the tropics and sub-tropics.
Ardisia crispa is a small shrub with persistent, deep green leaves and lovely scarlet berries which hold for almost six months and add a bright touch the whole winter.
This, as well as other species, for example the very similar A. crenata from south-east Asia and Japan, has one biological peculiarity: the edges of the leaves are crinkled and thickened. These thickened edges are inhabited by colonies of bacteria (Bacillus foliicola) which live in a symbiotic relationship with the leaf. This association is apparently justified for in experiments where the leaf margins were systematically removed the plants did poorly, even in conditions that were otherwise optimal.
Particularly good for the indoor glasshouse is Ardisia malouiana from Borneo. It is a low shrub with large, lanceolate leaves up to 25 cm (10 in) long, coloured dark velvety green on the upper surface with a long whitish-grey blotch by the midrib. In the juvenile stage they are deep red on the underside.
Ardisia crispa and like species should he grown in a humusyenriched with peat or John Innes potting compost. They are propagated quite readily by means of cuttings or seeds sown in winter in a warm propagator (best of all 25°C [77°F]). Before sowing they should be cleaned of all bits of pulp which might easily cause them to become mouldy.