Crassulas are amongst the easiest succulents to cultivate and this species is no exception. However, being monocarpic, it is not likely to live longer than three or four years. Sometimes it will send up a side shoot from the base after flowering and live for another season or two. The secret code for success is very well-drained gritty soils with a low organic content, good ventilation and very bright light which is essential.

Being a dwarf novelty plant, it is recommended to cultivate this species in a pot rather than the open soil. A sunny windowsill should therefore work well, but to keep the plant naturally compact, growing it outdoors in the full sun is recommended. Water sparingly and only when the plant becomes soft to the touch. As they are so drought-adapted their watering requirements are minimal. Overwatering is the easiest way to kill this plant as it will become susceptible to fungal attacks which result in rotting. Feeding is not necessary and will only cause lush growth which will ruin the refined nature of the plant.

Because this plant is single-stemmed and monocarpic, propagation by vegetative means (leaves and stems) is difficult. By far the easiest method of propagation is by seed. Seed would have to be harvested from the plant shortly after it ripens. If not collected promptly the seed will be lost because it is shed as soon as the fruits dry and open.

Crassula congesta is self-fertile, so seed can be obtained even from a single clone. Seed should be sown in autumn. Mix the dust-like seed with a small quantity of fine sand. Fill a pot or tray with the same gritty medium used for the mature plants and spread the seed/sand mixture thinly over the surface. Water immediately, preferably from below by standing the pot in a tray of water every few days. Keep the soil moist like this for the first month or so and always ensure good air movement, i.e. it is definitely preferable to keep the tray outdoors than in. Before long, tiny green plantlets should appear on the soil surface. Start to let the soil dry out between waterings. The use of a damping-off fungicide is advisable, and to aid rapid maturation, a weak liquid fertilizer could be used. Soon the plants will bulk up and if one achieves the ideal growing conditions, one can raise many thousands of plants like this.