This species is easily cultivated in a free-draining medium such as equal parts of river sand, loam, and sifted, acid compost. The bulbs are best planted with their necks fully exposed above soil level. It is an ideal subject for shallow containers as well as for rockeries, in positions receiving sun for at least half the day during the winter growing season. The bulbs cannot survive long wet periods during the summer dormant period and must be kept as dry as possible during this time. When watering actively growing bulbs, it is always best to water heavily at well-spaced, regular intervals, as opposed to superficial, infrequent watering. During the growing period, a heavy watering every two weeks is suggested, allowing the soil medium to dry out almost completely in between. No liquid or granular fertilizers are recommended for any Nerine species as these have the effect of encouraging luxuriant leaf growth at the expense of flowers.

Although regarded as the most beautiful of all the nerines, and the second-most widely grown species after Nerine bowdenii, Nerine sarniensis is also the most notorious for erratic flowering behaviour. Mature bulbs do not flower reliably every year, but it would seem that certain forms are naturally much more floriferous than others. Nerine sarniensis is not hardy in countries with very cold winter conditions, where it is best grown as a container subject in the cool greenhouse.

For the home gardener, propagation of Nerine sarniensis is best by means of seed and offsets. Seeds are sown as soon as they are easily detached from the capsules, in a sandy medium such as equal parts of coarse river sand and finely sifted compost, in deep seed trays. Cover the seeds with a 2-4 mm layer of sowing medium, place in a shaded spot and water well with a fine rose. Withhold any further watering until the first leaves appear, then water well every two weeks. Seedlings usually flower for the first time during their third or fourth growing season.

Offsets are best separated from mature bulbs in early autumn, and are ready to be removed when they are easily separated by gentle tugging. They should not be forcibly broken away as this may excessively damage the basal plate of the mother bulb. The separated offsets should be replanted immediately to prevent the brittle, fleshy roots from drying out. The most important pest affecting Nerine sarniensis is lily borer (Brithys crinii), also known as amaryllis caterpillar. Lily borer caterpillars can be picked off by hand or be sprayed with a carbaryl-based insecticide like Carbaryl. They are most prevalent on Nerine sarniensis from early to late spring.