Scientific Name
Euphorbia mammillaris L.
Common Name(s)
Indian Corn Cob, Corn Cob Plant, Corncob Euphorbia, Corncob Cactus
Synonym(s)
Often misspelled Euphorbia mamillaris
Scientific Classification
Family: Euphorbiaceae
Subfamily: Euphorbioideae
Tribe: Euphorbieae
Subtribe: Euphorbiinae
Genus: Euphorbia
Description
Euphorbia mammillaris is a short-stemmed dioecious succulent shrublet that forms dense clusters of many erect deep green stems with "spines," which are solitary sterile peduncles. The stems are club-like, ribbed, up to 14 inches (35 cm) tall, and up to 2.4 inches (6 cm) in diameter. The spines are occasionally present and scattered, thick, whitish, and up to 0.4 inches (1 cm) long. Leaves are small, green, and ephemeral. The plant produces yellow solitary cyathia at the tip of each stem in late winter to early summer.

Hardiness
USDA hardiness zone 9a to 11b: from 20 °F (−6.7 °C) to 50 °F (+10 °C).
How to Grow and Care
Euphorbias are very easy to care for. They require a little pampering to become established, but once they are, they are self-sufficient. In fact, more die from too much care and watering than from neglect. Euphorbias need well-draining soil and lots of sunlight. They are not particular about soil pH, but they cannot tolerate wet soil. Unlike most succulents, Euphorbia does not handle long periods of drought well. It may need weekly watering during the summer. Water whenever the soil is dry several inches below the surface. Water deeply, but don't let them sit in wet soil, which can cause root rot. Add some organic matter or fertilizer to the planting hole. Feed with a half-strength fertilizer monthly if you are growing them in containers or your soil is poor.
Euphorbia can be grown from seed, but they can be difficult to germinate (or even find). It is usually propagated by cuttings. This can be tricky because of the exuding sap. Rooting hormone is recommended with Euphorbias. They tend to grow problem-free, but there are a few pests and diseases to be alert for.
See more at How to Grow and Care for Euphorbia.
Origin
This species is native to South Africa (Cape Province).
Cultivars
Links
- Back to genus Euphorbia
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus