The best way to propagate the Melianthus elangatus is by seed. The seeds are collected from the plants when the fruits begin to turn brown, before the capsules dry out (October and November) and release the seeds. Remove the seeds and store them in a cool, dry place for autumn sowing. The embryo is fully developed when the seeds are smooth, black, plump and rounded. These are the seeds that are ready to be sowed. Prepare a well-drained sowing mixture and place your seeds on it. Cover the seeds to a depth that is the same size as the seeds, this will allow your seeds to receive enough oxygen and germinate in time. The seeds germinate in the fourth week, and monitoring of the seedlings is essential to keep the soil moist but not dry until the plants have reached the height for potting up. The seedlings take two to three years before they are large enough to transplant into the garden.

We have not propagated Melianthus elongatus by cuttings. However, it should be possible since M. major is easily propagated by cuttings.

The branches produced from the racemes seem weak and floppy. These branches should be pruned and other branches should be slightly pruned in mid- to late summer to create new shoots and give the plant vigorous growth and a compact shape. The older leaves become infested with rust and this could be prevented by applying a preventative fungicide.