Scientific Name
Euphorbia grandicornis Goebel ex N. E. Br.
Common Name(s)
Cow's Horn, Cow's Horn Euphorbia, Big Horn, Big Horned Euphorbia, Big Horned Spurge
Synonym(s)
Euphorbia grandicornis subsp. grandicornis
Scientific Classification
Family: Euphorbiaceae
Subfamily: Euphorbioideae
Tribe: Euphorbieae
Subtribe: Euphorbiinae
Genus: Euphorbia
Description
Euphorbia grandicornis is a succulent shrub with erect, green, 3- to 4-winged branches with a zigzag pattern and paired spines along the edges. The branches can grow up to 6.6 feet (2 m) tall and 4 inches (10 cm) wide. The spines are gray to brownish, up to 3 inches (7.5 cm) long, and arranged in pairs. The tiny leaves between the spines appear in summer and drop off later.
During late spring, brilliant yellow cyathia appear in groups of 3 along the tip of the stem. The central cyathium is stalkless and composed of only male flowers, while the other two are stalked and bisexual. The fruits are purple, quite attractive, 3-lobed capsules.
Etymology
The specific epithet "grandicornis (gran-dih-KOR-nis)" means "large-horned" and refers to the pairs of long spines.
Hardiness
USDA hardiness zones 10a to 11b: from 30 °F (−1.1 °C) to 50 °F (+10 °C).
How to Grow and Care
Euphorbias are very easy to care for. These plants 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.
These succulents can be grown from seed, but they can be difficult to germinate (or even find). They are 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.
Learn more at How to Grow and Care for Euphorbia.
Origin
Euphorbia grandicornis is native to South Africa, Swaziland, Mozambique, and Kenya.
Hybrids
Links
- Back to genus Euphorbia
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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