Agapanthus campanulatus is easy to grow. It requires rich, well-drained soil with ample compost (decayed organic matter) and plenty of water in summer. It does well in full sun, or semi-shade. It does not mind irrigation during its winter dormant period and does very well in the winter rainfall Western Cape, provided it is planted in well-drained soil.

To get the best out of Agapanthus campanulatus,  feed generously every spring and water well during spring and summer. Take note that unlike the evergreen agapanthus that need to be lifted and divided every four years or so to ensure optimal flowering, Agapanthus campanulatus, and all the other deciduous species, require a period of settling in and may not flower very well in their first year after being re-planted. It is best to leave them undisturbed for up to six years.

A. campanulatus is frost hardy, and should be able to survive in permanent outdoor cultivation in areas with a winter minimum of -7°C / 20° F (zone 9), although in regions that dip to -5° C / 23° F and below for long periods the plants should be mulched thickly with a protective layer of leaves/straw/hessian.

A. campanulatus is ideal for mass displays and makes a good groundcover in light shade under trees or planted in clumps in the herbaceous border. It is suitable for pot cultivation and is an excellent cutflower, either whole heads, or individual flowers in small arrangements, or wired and used in bouquets and posies.

Propagation is by seed or division. Because Agapanthus hybridise freely with each other, and are all in flower at the same time, you can be sure that there will be hybrids from seed harvested in the garden. To get pure seed of Agapanthus campanulatus it would have to be habitat collected or pollinated under strictly controlled conditions.

Seed can be sown fresh, in late summer/autumn, but in cold climates it can be kept refrigerated (not frozen) and sown in spring. It must be kept in the refrigerator or it will perish.

Seed should be sown in deep (10 cm) trays, in a mixture of equal parts river sand and fine compost, and kept semi-shaded and moist. Seed germinates readily within six to eight weeks. The seed should be sown thinly as the seedlings will stay in the tray for their first year. Seedlings should be potted up into individual containers during their second year and can be planted into the garden or permanent pots in their third year. Flowering can be expected from their third or fourth year.

Clumps can be lifted and divided in spring just before active growth begins, and remember it is best not to lift them too frequently, as flowering will be adversely affected.

Agapanthus campanulatus is generally pest- and disease-free. Foliage may be attacked by red spider mites, thrips, and mealy bug but need only be sprayed if infestation is severe. Agapanthus are famous for harbouring snails, although the snails do not seem to cause any damage to the plants themselves. The best way to combat them is to remove them by hand or to keep ducks. Botrytis, visible as brownish lesions, may attack the flowers preventing them from opening. There is no cure, it can only be prevented by spraying before and after the buds break open. The foliage may be attacked by the fungus Macrophoma agapanthii causing die-back of the leaves, and in severe cases this can be combatted with a fungicide such as mancozeb or captab as a full cover spray.