Species · genus Euphorbia · Euphorbiaceae
Cow's Horn Euphorbia
Euphorbia grandicornis Blanc
Also known as: Cow Horn Euphorbia · Big Horned Euphorbia
Cultivars of E. grandicornis
The named forms growers keep — each with its own page, each honest about how much we know.
No named cultivars catalogued under E. grandicornis yet. When growers document a stable, named form, it earns its own page here.
Guide
The species-level account. Cultivar pages build on this and say where they differ.
A Spined Succulent Shrub
Euphorbia grandicornis is a succulent shrub in the spurge family, Euphorbiaceae, grown for its thorny, angular stems rather than for flowers or foliage. Like other members of its genus it carries milky sap and produces small flowers set within cupped bracts.
Source: RHS
Southern African Native
This species comes from a stretch of southern Africa running from southern Mozambique down into KwaZulu-Natal, with its native range also touching Eswatini and the Northern Provinces. It grows there in desert and dry shrubland habitats, and it has additionally been introduced into the Canary Islands. It was first published under the name Euphorbia grandicornis by Blanc in 1888.
Source: Kew
Two Recognised Subspecies
Botanically, Euphorbia grandicornis is treated as a succulent shrub, and taxonomists recognise two accepted infraspecific forms: subspecies grandicornis and subspecies sejuncta. The latter, described by Leach in 1970, is confined to north-central Mozambique, again in desert or dry shrubland biome, distinguishing it geographically from the broader-ranging main subspecies.
Source: Kew
Care recipe
The species record — the baseline every cultivar inherits unless it says otherwise.
Care notes are early — not yet verified
- Light
- ai:claude-opus-4-8
- Water
- ai:claude-opus-4-8 (range 14-30d)
- Humidity
- ai:claude-opus-4-8
- Soil
- ai:claude-fable-5
- Care
- ai:claude-fable-5
Direct sun
≈ every 30 days
Low — average room
13–32 °C
Very gritty mineral cactus and succulent mix
Stem cuttings, dried to callus firmly first
Sparse cactus feed once or twice in summer
Slow
Rarely flowers indoors; grown for sculptural spined stems
Toxic to cats & dogs & humans
Euphorbiaceae produce an irritant milky latex that can harm skin, eyes, and mucous membranes. This is where toxicity lives: every cultivar of this species inherits it and none can override it.
Reference images
Every image credited. Licenses link to their deeds.
Sources: ai:claude-opus-4-8 · ai:claude-opus-4-8 (range 14-30d) · ai:claude-fable-5 · ai:claude-opus-4-8 (family inference)
Kept true by its growers
Every fact here carries its source. Grow Cow's Horn Euphorbia yourself? What you’ve observed — how it drinks, how it holds its color, a name that’s off — and a clear photo of your plant are exactly what keep this page honest. Contributions are reviewed before anything changes.
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