Spiny, heavily branched succulent Euphorbia which can grow to the size of a bush or small tree, given time and space. Very common in cultivation. The branches are upright, running mostly vertical, so the plant does not develop much spread until old age. (This upright branching may be useful to distinguish young plants from the similar-looking E. lactea.)

This plant has a mottled stem and small leaves which appear during active growth but do not last long. There is a red-tinged version called rubra, among other forms.

Handle cuttings with caution. Wear gloves, use sharp tools, and avoid touching the fresh sap, which may be an extreme irritant, made much more dangerous when the skin is broken by spines.

Best form in strong light. Growth may be seriously retarded by underpotting. This species does not flower, and this strange behavior is likely a product of domestication.

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