Serruria elongata can make a very ornamental garden shrublet, although it is rarely cultivated. In cultivation, it usually only survives for a few years if successfully cultivated. Throughout the growing season, Serruria elongata requires sunlight and well-drained soils that provide balanced moisture supply. Plants growing in well-watered, elevated and montane habitats tend to have longer peduncles than those growing at the coast that experience more extreme temperatures and strong winds. In the same way as other proteas, serrurias are susceptible to phytophthora diseases, which affect the root system and can kill the plants at any stage of development. Plants are best cultivated where they will receive the least amount of root disturbance. Remove all infected plants from the garden and destroy them completely.

Propagation of Serruria elongata can be done either from the small, russet seeds or from cuttings. Between summer and autumn, take semi-hardwood cuttings from mature plants. Place the stem cuttings in a growing house or greenhouse at a warm temperature and apply rooting hormone to promote root growth. To prevent diseases like phytophthora root rot, treat with fungicide. Transplant the cuttings into a 1kg bag with a soil mixture of fine-milled bark and fynbos sand after three weeks. They should be grown on until they are ready to be planted in the garden.

Sow the seeds in autumn, to allow for higher daytime temperatures and cooler night time temperatures that will trigger germination. Sow seeds in a seed tray with fine-milled bark and fynbos sand in a well-drained medium. Transplant the seedlings into 1kg bags and treat them with a fungicide to prevent diseases. The young plant should be watered in the morning and fed with organic-based fertilizer.