Like most ericas, the cube heath prefers soil with an acidic pH ranging from 5.5-6.7 and a sunny position. Ericas can grow in a variety of habitats but always prefer soil with good drainage. Prune the plant lightly after flowering, this will encourage the development of new shoots, pruning will also remove dead or damaged branches. Apply an organic liquid fertiliser such as a fish emulsion when planting in pots. Erica cubica can be grown by taking ± 40-50 mm long cuttings 2 months after flowering, from semi-hardwood, heel or nodal cuttings. Use a rooting medium of fine-milled bark and perlite balls at a 50:50 ratio to improve the chances of successful rooting.

Vegetative propagation of this plant will result in much faster development from a rooted cutting to a young plant, although seed sowing is ideal but usually a slower process before it reaches the seedling stage. Erica cubica can be successfully grown in normal greenhouse conditions and usually roots well when supported by a hot bench maintained at a constant bottom heat of 24°C. Open-air mist spray units can also create ideal conditions when propagating by cuttings, to prevent the cuttings from drying out too quickly or overheating they can be lightly shaded during summer.

Transplant the rooted cuttings into small pots, about 9 cm, and when the roots are well-developed transplant them into half-litre plastic bags containing 7 parts milled bark and 3 parts sand (the same mix as for pots) and water thoroughly. Feed with an organic liquid fertilizer, preferably a fish emulsion type, every 2 weeks and shade lightly for a month, thereafter it can be placed in full sun conditions. The cuttings will be ready for planting after about 3 months, care must be taken not to damage the fine root hairs when transplanting.

Harvest seeds after flowering when the seed capsules have dried, before dropping to the ground. Take a branch with old flowers and tap gently on the palm of your hand. If the seed falls into your hand then collect the stem with old flowers and place them into a paper packet to dry. The old flowers containing the fruits should be dried and then rubbed through a sieve. The resultant mix may be winnowed to separate the seed from the trash.

Sow seeds in autumn (April and May), when the temperature starts to drop naturally. Use seed trays about 100 mm deep, filled with equal parts of river sand and sifted composted bark and ensure that the trays drain well. Use fine river sand to mix with the seeds this will prevent the seeds from being sown too densely. Broadcast the seeds on top of the levelled mix, at this stage, you may cover it lightly with some of the mixed sand. Treatment of the seeds with ‘fynbos smoke’ or smoke extract greatly enhances germination. Water carefully with a fine hose because seedlings will be washed from the tray. Do not expose the seedlings to direct sunlight and rain, over-watering causes damping off The seeds will start to show signs of germination after about 2 months. Transplant young plants into multi-trays or small pots as soon as they reach a height of about 10 mm.

Apply an appropriate organic contact or systemic pesticide to control mealybug and scale insects. Fungal attacks can be prevented by not sowing seeds too densely and by ensuring good air circulation in the propagation unit.