This plant is fast growing and long-lived. It prefers a permanent spot where it will not be disturbed; constant digging up and moving damages its perennial roots and reduces flowering. It can be grown outdoors in mild parts of the Northern Hemisphere, but needs protection in very cold areas. It can be cultivated in a large container, but must be kept well watered and fertilised regularly.

Grow Crinum macowanii in full sun, in fertile soil. It needs regular heavy watering during its summer growing period and thrives in a moist position, e.g. beside a stream, river or pond or on the edges of a vlei and is ideal for wet parts of a garden. It prefers to be dry during its winter dormant period but will survive winter irrigation and/or rain provided the soil is very well drained. It is a heavy feeder and benefits from regular feeding and generous applications of well-rotted compost. 

Propagate by seed or the removal of offsets. Crinum macowanii produces a large number of seeds and they germinate readily. Seed is perishable and must be sown as soon as it is ripe, in deep seed trays, in well-drained sandy soil enriched with compost and placed in a warm, sunny spot and kept moist. Seeds germinate in a week or two. Seed-grown plants should flower from their third year. Although Crinum macowanii does not form offsets readily, remove offsets after flowering or while the plant is dormant.

Watch out for the Amaryllis Lily Borer, and slugs and snails can cause damage.