Scientific Name
Euphorbia greenwayi P.R.O.Bally & S.Carter
Synonym(s)
Euphorbia greenwayi subsp. greenwayi
Scientific Classification
Family: Euphorbiaceae
Subfamily: Euphorbioideae
Tribe: Euphorbieae
Subtribe: Euphorbiinae
Genus: Euphorbia
Etymology
The specific epithet "greenwayi (GREEN-way-eye)" honors Percy (Peter) J. Greenway (1897–1980), a British botanist in Tanzania from 1928 and in Kenya from 1957.
Origin
Euphorbia greenwayi is native to Tanzania. It grows on rocky outcrops only in one location in the Iringa escarpment.
Description
Euphorbia greenwayi is a basally branching succulent with sharply, 4-angled, bluish green branches, usually with darker blotches along the angles with shallow to prominent teeth up to 0.6 inches (1.5 cm) apart. The elongated spine shields extend downward to or just above the flowering eye, often forming a continuous horny reddish brown margin. The spines are slender, red, becoming black with age, and can grow up to 0.4 inches (1 cm) long.
The pinkish flowers have long, thin, red stigma lobes and appear in spring.
How to Grow and Care for Euphorbia greenwayi
Light: This succulent is a sun lover. Place your indoor E. greenwayi in a sunny window. You may place the pot on the balcony or in the garden from spring to fall. Increase sun exposure gradually to prevent sunburn.
Soil: E. greenwayi requires well-drained soil. Use a commercial potting mix formulated for succulents, or make your own.
Temperature: High summer temperatures are not a problem, but low winter temperatures can damage or kill your plant. E. greenwayi can withstand temperatures as low as 30 °F (-1.1 °C). USDA Plant Hardiness Zones 10а to 11b, 30 to 50 °F (-1.1 to 10 °C).
Watering: From spring to fall, water when the top inch (2.5 cm) of soil feels dry. Reduce watering in winter. Give it just enough water to prevent wilting. The best time of the day to water your E. greenwayi in the warm season is the evening.
Fertilizing: Plants in a pot need regular feeding. Apply a balanced fertilizer in a 10-10-10 NPK formulation, diluted to 1/4 strength weekly during the growing season.
Repotting: E. greenwayi will benefit from repotting, but it does not need to be repotted yearly. When your plant is outgrowing its pot, it is time to repot it in a larger pot and give it a fresh potting mix. The repotting is best done in early spring, at the beginning of the growing season. Wear gloves, protective clothing, and appropriate eye protection when repotting this succulent.
Propagation: The easiest and fastest propagation method for this plant is by cuttings. It can also be grown from seeds, but it can be difficult for seeds to germinate. The best time to take cuttings is in spring or summer. Sow the seeds in spring.
Learn more at How to Grow and Care for Euphorbia.
Toxicity of Euphorbia greenwayi
E. greenwayi produces a toxic white milky sap that can irritate the skin and eyes. Therefore, keeping your plant away from children and pets is best.
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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