Scientific Name
Euphorbia neohumbertii Boiteau
Synonyms
Euphorbia neohumbertii var. neohumbertii
Scientific Classification
Family: Euphorbiaceae
Subfamily: Euphorbioideae
Tribe: Euphorbieae
Subtribe: Euphorbiinae
Genus: Euphorbia
Description
Euphorbia neohumbertii is a succulent plant with erect, 4-sided stems and large, green leaves that grow on the top of the stems. It grows up to 3 feet (90 cm) tall. In the winter, when leaves drop, very prominent scars are left on the stems. In the spring, the stems are topped with scarlet flowers tipped in yellow.

Hardiness
USDA hardiness zones 9b to 11b: from 25 °F (−3.9 °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 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. If you are growing them in containers or your soil is poor, feed with a half-strength fertilizer monthly.
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.
See more at How to Grow and Care for Euphorbia.
Origin
Euphorbia neohumbertii is native to Madagascar.
Links
- Back to genus Euphorbia
- Succulentopedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus