Euphorbia richardsiae

Origin

Euphorbia richardsiae is native to Northern Malawi in East Africa. It is a geographically restricted species, specifically known from the Mzimba District and the Nkhalapya (Kalapya) Dome. The species is named after Mary Richards, a prolific botanical collector who documented much of the flora in this region. There are two recognized subspecies: the nominate subsp. richardsiae and the more vigorous subsp. robusta.

Habitat

This species is typically found in montane and sub-montane zones, growing at altitudes between 1,350 and 2,000 meters. Its natural habitat consists of granite outcrops and rocky crevices within dry shrubland biomes. In these environments, the plants grow in thin layers of grit and organic leaf mold, often exposed to high light intensity and distinct seasonal cycles of moisture and drought.

Description

Euphorbia richardsiae is a dwarf, spiny, succulent shrublet that stands out for its compact and geometric growth.

• Growth Habit: It forms a small, branched shrub typically reaching 10–15 cm in height (though subsp. robusta can grow slightly larger and more upright). Its growth is densely clustered, making it look like a miniature desert tree.

• Stems: The branches are typically 4 to 5-angled, with a distinct grayish-green to olive skin. The angles are sharp and neatly lined with spine shields.

• Spines: It features neat, dark-colored spine shields (up to 8 mm long) that bear pairs of sharp spines (3–6 mm). The arrangement of these spines gives the plant a very orderly, architectural texture.

• Flowers: The cyathia (flowers) are small and usually yellowish-green, appearing at the tips of the branches. While not visually showy, they add to the plant's intricate detail during the blooming season.

• Cultivation: It is a slow-growing species that requires a very porous, mineral-heavy potting mix. It prefers bright, indirect light and should be allowed to dry out completely between waterings to mimic its rocky, well-drained native habitat.

Safety Information: As with all Euphorbia species, this plant produces a caustic white latex (sap) if cut or damaged. This sap is a skin and eye irritant and is toxic if ingested. Always wear gloves when pruning or repotting.