Water sparingly, allowing the soil to dry out completely between waterings. Overwatering is a common cause of root rot for Alluaudia humbertii.

During winter dormancy, reduce watering significantly to almost none, providing just enough to prevent the tubers from desiccating.

Pruning is generally not required for aesthetic reasons. Remove any dead or damaged stems promptly to maintain plant health and prevent potential disease.

If necessary to control size or shape, prune in spring before active growth begins.

Alluaudia humbertii is best propagated from stem cuttings taken in spring or early summer. Allow the cuttings to callus over for a few days before planting them in a well-draining succulent or cactus mix.

Rooting can be slow, so patience is key.

Repot young plants annually or every two years, and mature plants every three to four years, preferably in spring. Use a gritty, fast-draining potting mix.

Ensure the pot has drainage holes to prevent waterlogging, which is detrimental to this species.