Euphorbia antiquorum aka Triangular Spurge

Euphorbia antiquorum is an easy-care succulent that thrives with minimal attention. It tolerates drought, poor soils, and some neglect, making it ideal for beginners or busy plant owners. The main care considerations are providing adequate sunlight, avoiding overwatering, and handling the plant carefully due to its toxic latex.

Euphorbia antiquorum is one of the largest tree euphorbias, typically reaching 5-7 metres (16-23 feet) tall with exceptional specimens growing to 20 metres. The stems are 5-7 cm thick, forming a loosely rounded crown through upward-curving branches. It grows at a moderate pace, taking 3-5 years to develop into an adequate landscape specimen.

Euphorbia antiquorum is frost-tender and requires minimum temperatures of 10°C (50°F). It can briefly tolerate temperatures as low as -1°C (30°F) but sustained cold will damage the plant. Indoors, it thrives at normal room temperatures between 15-27°C (60-80°F). In winter, reduce watering significantly when temperatures drop.

Propagate Euphorbia antiquorum through stem cuttings taken during the growing season. Cut a section of stem and allow it to dry in a shaded area for 1-2 weeks until the cut end calluses over—this prevents rot. Plant the dried cutting in extremely well-draining soil. Water sparingly until roots establish. Seeds can also be used but cuttings are more reliable and faster.

Yes, Euphorbia antiquorum produces small cyathia (specialized flower structures) that are yellowish-green to pinkish in color. They appear year-round in terminal or axillary positions, either singly or in clusters of 3-4. The flowers are filled with nectar that attracts bees. After pollination, capsular fruits develop that are green initially and turn deep red when mature.

Euphorbia antiquorum is pollinated primarily by insects, especially bees attracted to the nectar-filled cyathia. The cyathia produce honey that draws pollinators to the plant. All cyathia are bisexual, containing both male flowers (with a single stamen) and female flowers (with three unfused styles) to facilitate successful pollination.

Euphorbia antiquorum can be grown outdoors year-round in USDA hardiness zones 10-11 where temperatures stay above -1°C (30°F). It thrives in hot, dry climates and makes an excellent specimen tree or protective hedge. In cooler climates, grow it in containers that can be moved indoors during winter. Choose a location with full sun and excellent drainage.

Euphorbia antiquorum requires minimal pruning. Remove any dead or damaged stems as needed. When pruning, always wear protective gloves and eye protection as the plant releases toxic white latex when cut. The latex can cause skin irritation and severe eye damage. Allow cuts to callus naturally and avoid watering the wounds.

Repot Euphorbia antiquorum every 2-3 years or when roots outgrow the container. Use a pot only slightly larger than the current one, as euphorbias prefer being somewhat rootbound. Choose terracotta or unglazed pots for better drainage. Use a cactus/succulent mix or add coarse sand to regular potting soil. Repot in spring at the start of the growing season.

Euphorbia antiquorum is generally pest-resistant, though it can occasionally attract mealybugs, spider mites, and scale insects. The most common problem is root rot from overwatering or poor drainage. Ensure soil dries between waterings and use well-draining potting mix. The toxic latex provides natural protection against many pests and herbivores.

In Ayurvedic medicine (where it's known as Snuhi or Tridhara), the latex has been used topically for piles, warts, skin lesions, and joint inflammation. It's traditionally applied for rheumatism, toothache, and to treat cutaneous infections. However, the raw latex is highly caustic and must be properly prepared by trained practitioners—undiluted application can cause severe burns and blistering.

Beyond ornamental use, Euphorbia antiquorum serves multiple purposes in its native regions. It's planted as protective hedging due to its spiny stems. The latex has been used as fish poison. Young shoots are reportedly eaten as a vegetable in some cultures, though this requires careful preparation due to toxicity. It's also valued in traditional medicine systems.