Erica: Greenhouse Plants
C – cool, minimum of 7°C (45°F)
Cool house Ericas are known as the Cape Heaths as most of them originate from South Africa. They are delightful small autumn and winter flowering shrubs which will do well if kept cool and moist never allowing theto become dry. They dislike lime so when potting choose a lime-free peat-based compost with plenty of sharp sand. During summer they can be temporarily moved to a cool shady spot outside. Most commonly grown is Erica X hyemalis. This has very fine lime-green foliage and quite large bell-shaped flowers of pink and white. Although it tends to be sold as a houseplant which is discarded after flowering, there are distinct benefits in adding it to a greenhouse display; flowers will last longer and with care the plant can be grown on from year to year in the cooler atmosphere. E. gracilis has rosy-red flowers although there is a white flowered form. This will grow to 45 cm (18 in) tall. E.pageana is a tall shrub of 1-1.2 m (3-4 ft). It produces bell-shaped yellow flowers during autumn. My favourite is E. canaliculata which is another tall one with pure white or occasionally pinkish flowers and black stamens.
The species with soft shoots should be cut back after flowering each year. The shrubbier woodier species however, do not respond so well to pruning and are best left. Seed sown during spring in a peat-based seed compost takes at least a month to germinate and must have light. It is a good idea to incorporate somefrom where heathers grow naturally into their compost at potting up time. Cuttings 2.5-5 cm (1-2 in) long of lateral growths from near the base of the shoots can be taken in summer.