Hypocalymma is a small genus of about 29 species, all of which occur naturally only in south Western Australia. H.angustifolium and H.cordifolium are the best known members of the genus and are widely cultivated. H.cordifolium is a small, spreading shrub from 0.5 to 1.5 metres high with small, oval or triangular-shaped leaves about 10 mm long. In late winter and spring small, white flowers appear singly or in small clusters along the stems. The flowers are about 5-10 mm in diameter.
This species has been in cultivation forr many years and is a popular garden plant for a range of climates. It is readily cultivated in humid, east-coastal areas where other species from the south west are often difficult to maintain. The plant requires well drained conditions in full sun or dappled shade and it is tolerant of at least moderate frost. Annual pruning will help maintain a dense, bushy growth habit. It is a good species for use as a low hedge. The flowering habit of H.cordifolium is not spectacular and the foliage is probably the most attractive feature of the plant. The cultivar ‘Golden Veil’ is especially attractive with variegated foliage in tones of cream and green, flushed with red when new.
Propagation can be carried out from seed and, based on experience with the related H.angustifolium, improved germination may be achieved using smoked water. Propagation from cuttings is the preferred method and cuttings strike readily from hardened, current season’s growth. Propagation from cuttings must be used for named cultivars such as ‘Golden Veil’ as these will not come true to type from seed.
Photo: Geoff Warn