Scientific Name
Euphorbia unispina N.E.Br.
Common Name(s)
Candle Plant
Scientific Classification
Family: Euphorbiaceae
Subfamily: Euphorbioideae
Tribe: Euphorbieae
Subtribe: Euphorbiinae
Genus: Euphorbia
Etymology
The specific epithet "unispina" (pronounced "un-ee-SPIN-a") means "having a single spine." It refers to the single spine per spine shield in this species, unlike many Euphorbia species, which typically have two spines per spine shield.
Description
Euphorbia unispina is a shrubby or tree-like succulent with a thick stem, usually with 3 to 4 cylindrical branches and wedge-shaped leaves arranged in a terminal rosette. It can grow up to 10 feet (3 m) tall. The branches are silvery-grey, with obscure tubercles arranged in spiral lines and spine shields with a single spine. The leaves are green, often with reddish margins. They can measure up to 4.8 inches (12 cm) long and 1 inch (2.5 cm) wide. The spine shields can reach a diameter of 0.4 inches (1 cm). The spines are dark grey, cone-shaped, and can grow up to 0.5 inches (1.2 cm) long. The older specimens can be spineless.
The flowers (cyathia) are yellow-green, 5-lobed, and appear at the end of the dry season before the new leaves appear. They can measure up to 0.2 inches (0.5 cm) in diameter. Usually, the cymes have three cyathia: one terminal and two lateral.
Origin
Euphorbia unispina occurs from Guinea and Mali east to southern Sudan. It grows on rocky hills in the savannah.
How to Grow and Care for Euphorbia unispina
Hardiness: USDA hardiness zones 9b to 11b: from 25°F (-3.9°C) to 50°F (10°C).
Euphorbias are very easy to care for. These plants need a little pampering to establish, but once they are established, they are self-sufficient. More die from overcare and overwatering than from neglect. Euphorbias need well-draining soil and lots of sunlight. They aren't particular about soil pH, but they can't tolerate wet soil. Unlike most succulents, Euphorbia does not tolerate long periods of drought. 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. If you are growing them in containers or your soil is poor, feed them with a half-strength fertilizer monthly.
You can grow these succulents from seed, but germination can be tricky (or even hard to find). They are usually propagated by cuttings. This can be tricky because they exude sap. Rooting hormone is recommended with Euphorbia. They tend to grow problem-free, but watch for a few pests and diseases.
Learn more at How to Grow and Care for Euphorbia.
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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