Euphorbia mammillaris L.
Corncob Cactus, Corn Cob Plant, Corncob Euphorbia, Indian Corn Cob
Euphorbia latimammillaris, Euphorbia mammillaris var. submammillaris, Euphorbia platymammillaris
Euphorbia mammillaris is a succulent shrublet with many erect, ribbed, club-like stems with lateral branches and irregularly scattered and spreading spines. It grows up to 12 inches (30 cm) tall. The chalky green stems have 7 to 15 ribs and can reach up to 2.4 inches (6 cm) in diameter in diameter. The spines are actually hardened peduncles. They are pinkish-white, about 0.8 inches (2 cm) long. The short-lived leaves are green and up to 0.25 inches (0.6 cm) long.
The plant produces a cup-shaped involucre of yellow fused bracts enclosing several greatly reduced male flowers and a single female flower at the tip of the stems from late winter to early summer.
Euphorbia mammillaris is native to South Africa. It grows on flats and stony slopes among bushes from Albertinia in Western Cape to Makhanda, also known as Grahamstown, in the Eastern Cape province.
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. 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 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.
- Back to genus Euphorbia
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
Click on a photo to see a larger version.