Crassula ovata ‘Horn Tree’

A cultivated form of the South African jade plant

‘Horn Tree’ is a cultivated selection of Crassula ovata.

The species is native to South Africa’s Eastern Cape and KwaZulu-Natal and extends into southern Mozambique. In the wild it grows in thicket, scrub and rocky places, where thick leaves and sturdy branches suit periods of limited rainfall.

Care for water-storing roots and leaves

Pruning and rooting horn-shaped branches

Tubular leaves and a branching crown make older plants top-heavy, so use a stable pot and prune selected long branches to retain a balanced tree form. Support Crassula ovata ‘Horn Tree’ by its trunk when moving the pot, clean smooth leaves with a soft brush or lightly damp cloth and keep oils or leaf-shine products off the waxy surface.

Humidity and airflow

Ordinary dry household air is appropriate for this succulent. Misting is unnecessary and can trap moisture between close-set leaves.

Sunlight for sturdy tubular leaves

Place Crassula ovata ‘Horn Tree’ at a bright south- or west-facing window with plentiful direct sun, or directly under a strong grow light. Acclimate the plant gradually before prolonged hot exposure behind glass.

Soak, then dry the woody jade roots

Wait until the substrate is dry through almost the full pot and the leaves are only beginning to lose their firm feel. Months of severe drought still cost fine roots and foliage, while constant moisture can rot the thickened base.

Lean feeding for sturdy horn-shaped growth

Use a balanced cactus or succulent fertiliser only while the plant is producing firm growth. Reduce the dose after repotting or when the plant receives only moderate light.

A stable pot for a miniature succulent tree

Repot Crassula ‘Horn Tree’ when roots circle tightly, the crown becomes unstable, water runs straight through channels or the mix has broken down. Let the substrate become nearly dry first, keep the root ball intact, trim only dead roots and wait several days before watering deeply if roots were damaged.

When the trumpet leaves or stems of Crassula ‘Horn Tree’ change

The trumpet-shaped leaves wrinkle or collapse

Wrinkled but firm horns usually mean the plant has used its stored water. If the mix is dry and the roots are sound, water thoroughly and let it drain. Translucent, mushy leaves on wet compost indicate excess water; check the roots and stem before giving another drink.

The red-rimmed tips turn bleached or corky

A red blush around the open horn tips is normal pigmentation. Pale tan patches appearing after a sudden move into strong sun are scorch. Acclimatise ‘Horn Tree’ gradually and leave dry scars alone. Soft brown tissue spreading inward from a tip suggests rot; harmless colour and sun scarring stay dry and firm.

New horns grow long, thin and widely spaced

Compact trumpet leaves become stretched when light is insufficient, and the branching top may lean under the weaker growth. Increase the light gradually, turn the pot and wait for firm compact growth before pruning. Existing elongated horns stay long and continue feeding the plant.

Raised corky spots appear on the leaves

Firm cork-like blisters can follow oedema, when roots take up water faster than the succulent leaves can use it, particularly in cool low light. Let the mix dry appropriately, improve light and drainage and avoid soaking a cold plant. Discard any diagnosis of oedema if the marks are soft, spreading or accompanied by a black stem.

The trunk base turns black or soft

A black, soft trunk base strongly suggests rot and needs prompt attention; normal woody ageing remains dry and firm. Remove the plant from the pot, cut above all discoloured or soft tissue and root a firm healthy section if possible. Dispose of collapsed roots and wet mix; a dark lesion that continues upward can destroy the remaining branches quickly.

Crassula ovata ‘Horn Tree’ is toxic to cats and dogs

• Keep this plant away from cats and dogs that may chew it.
• Chewing may cause mouth irritation, vomiting, stomach pain or weakness.
• Contact a veterinarian after pet ingestion. Seek medical advice if a person swallows the plant and becomes unwell.

What does the name Crassula ovata mean?

Crassula comes from the Latin crassus, meaning thick. The epithet ovata means egg-shaped and describes the fleshy leaves of the typical species.

Carl Linnaeus established the genus Crassula in 1753 in Species Plantarum, page 283.

Philip Miller first described it as Cotyledon ovata in 1768 in The Gardeners Dictionary, eighth edition, n.° 8. George Claridge Druce later placed it in Crassula as Crassula ovata in 1917 in Report of the Botanical Society and Exchange Club of the British Isles, volume 1916, page 617.