Euphorbia ingens – Plant Description

Euphorbia ingens, commonly known as the Candelabra Tree, Cowboy Cactus, or Naboom, is an impressive succulent tree from the Euphorbiaceae family. Native to Southern Africa, it is widely admired for its sculptural, cactus-like form.

Despite its resemblance to a cactus, Euphorbia ingens is in fact a succulent euphorbia. It develops thick, upright, columnar stems with four or five ridged sides, edged with small spines. Mature specimens branch repeatedly from the upper portion of the trunk, forming a distinctive candelabra-like silhouette. Indoors, the plant’s upright form makes it a bold architectural feature, while in the wild it can grow into a tree over 10 metres tall.

The stems are a deep green, sometimes with lighter markings, and in its natural habitat, mature plants produce clusters of small yellow-green flowers in autumn. Indoors, flowering is rare, but the striking, statuesque appearance of this plant more than compensates.

Euphorbia ingens – Care Guide

Light

Thrives in bright, direct light. Place near a sunny south- or west-facing window indoors. Outdoors, it flourishes in full sun. Insufficient light may cause weak, leggy growth.

Watering

Water sparingly. During the growing season (spring and summer), water only when the soil has completely dried out, then soak thoroughly. In autumn and winter, reduce watering significantly, as the plant goes semi-dormant. Overwatering is the most common cause of failure, leading to root or stem rot.

Temperature and Humidity

• Temperature: Prefers warm conditions between 18–28°C. Protect from frost; never allow temperatures to drop below 10°C.

• Humidity: Tolerates low humidity very well, making it suitable for centrally heated homes.

Soil and Potting

Requires a free-draining succulent or cactus mix. Adding extra sand, grit, or perlite improves drainage. Choose a pot with good drainage holes, ideally a heavy one to balance the plant’s height. Repot every 2–3 years in spring if root-bound.

Feeding

Feed monthly in spring and summer with a diluted cactus fertiliser. Stop feeding in autumn and winter.

Pruning and Maintenance

Pruning is rarely needed but can be done to shape the plant. Be cautious when cutting, as Euphorbia ingens produces a toxic white latex sap that is irritating to skin and highly poisonous if ingested. Always wear gloves and avoid contact with eyes or skin.

Growth and Maturity

Indoors, it typically reaches 1.5–3 metres, depending on conditions and pot size. Outdoors in its native habitat, it can become a massive tree-like succulent. Its branching candelabra form develops slowly over time, adding to its dramatic appeal.

Common Issues

• Yellowing or soft stems: Usually caused by overwatering.

• Leggy growth: A sign of insufficient light.

• Pests: Rare, but may attract mealybugs or scale insects.

Background and Benefits

Euphorbia ingens is not only an architectural showpiece but also deeply rooted in African culture, where it has been traditionally used for medicinal and practical purposes (though caution is needed due to its toxic sap). Today, it is celebrated as a striking ornamental specimen, bringing dramatic, desert-like beauty to homes and conservatories.

✅ Quick Care Summary

• Light: Full sun or bright, direct indoor light

• Water: Only when completely dry; very sparing in winter

• Temperature: 18–28°C; avoid below 10°C

• Humidity: Low to moderate; very tolerant

• Soil: Free-draining cactus/succulent mix

• Feed: Monthly in spring/summer

• Growth: Upright, candelabra-shaped succulent; 1.5–3 m indoors