Allow the soil to dry out completely between waterings. Euphorbia ritchiei is drought-tolerant and prone to root rot if overwatered.

Water sparingly during winter dormancy, providing just enough to prevent the soil from becoming bone dry. Ensure good drainage to prevent waterlogging.

Prune to maintain shape or remove dead/damaged stems. Use a sharp, clean knife or shears. The milky sap can be an irritant, so wear gloves and eye protection.

Pruning can be done at any time, but is best done in spring before active growth begins. Dispose of cuttings properly.

Propagate from stem cuttings in spring or summer. Allow cuttings to callus over for a few days to prevent rot before planting in well-draining soil. Roots typically form within a few weeks.

Use sterile tools and wear gloves due to the irritating sap.

Repot every 2-3 years or when the plant becomes root-bound. Use a well-draining potting mix, such as a cactus or succulent blend. Choose a pot slightly larger than the current one.

Repot in spring, handling the plant carefully due to its sharp spines and irritating sap.