How to grow Kransberg Agapanthus

Agapanthus coddii is easy to grow. It requires rich, well-drained soil with ample compost (decayed organic matter) and plenty of water in summer¹. It does best in full sun, is not at its best in semi-shade but will still do well in light shade for about half the day¹. It does not mind irrigation during its winter dormant period, and also does very well in the winter rainfall areas, such as the Western Cape¹. In order to get Agapanthus coddii to flower well, it is crucial that it is fed generously every spring and watered well during spring and summer. As with most plants they benefit most from regular (e.g. weekly) deep drenching as opposed to frequent superficial waterings. Plant Agapanthus coddii so that the rootstock is just underground. Take note that unlike the evergreen agapanthus that need to be lifted and divided every four years or so to ensure flowering, Agapanthus coddii, 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 years¹. Agapanthus coddii 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 / hessian¹.

They are 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 severe¹. 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 can be combatted with a fungicide like mancozeb or captab as a full cover spray¹.

Seed can be sown fresh, in late summer – autumn, but in cold climates it can be kept refrigerated (not frozen) and sown in spring¹. It must be kept in the refrigerator or it will perish¹. 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 moist¹. 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 year¹.

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 coddii it would have to be habitat collected or pollinated under strictly controlled conditions¹.

These estimates for how long Kransberg agapanthus takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

The name Agapanthus comes from the Greek agape, meaning love, and anthos, meaning flower, translating broadly as the flower of love¹. The species Agapanthus coddii is named after Dr. L.E.W. Codd, botanist and director of the Botanical Resarch Institute in Pretoria from 1963-1973¹.

Codd's agapanthus

Agapanthus coddii Leighton

² Agapanthus coddii on PlantzAfrica