The Candelabra Cactus, a striking houseplant, brings a unique architectural form to any indoor setting. Its distinctive upright growth and branching structure make it a focal point. This resilient succulent is an excellent choice for those seeking a low-maintenance yet visually dramatic plant to enhance their living spaces.
Understanding the Candelabra Cactus
The Candelabra Cactus, scientifically known as Euphorbia trigona, is also commonly referred to as the African Milk Tree, Cathedral Cactus, and Friendship Cactus. Despite its common name, it is a succulent and not a true cactus. Its tall, upright stems are typically triangular in cross-section, inspiring its species name “trigona”.
Its green stems have ridged edges adorned with small, sharp thorns and small leaves. Some cultivars, such as ‘Rubra’, display reddish hues. Native to central Africa, this plant is adapted to arid conditions.
Essential Indoor Care
Light Requirements
The Candelabra Cactus thrives in bright, indirect light indoors. Placing it near a south or west-facing window is ideal. While it appreciates bright conditions, prolonged exposure to intense, direct midday sun can cause scorching or brown spots on its stems. Insufficient light, however, may lead to etiolation, resulting in thin, leggy growth.
Watering Practices
This succulent is drought-tolerant, storing water in its fleshy stems. The “soak and dry” method is recommended: water thoroughly until it drains from the pot’s bottom, then allow the soil to dry completely before watering again. Overwatering is a common issue that can lead to root rot, especially during cooler months when the plant’s growth slows. In winter, watering should be reduced to as little as once a month to prevent excessively damp soil.
Soil and Drainage
Proper soil drainage is essential for the Candelabra Cactus to prevent root rot. Use a well-draining cactus or succulent potting mix. You can enhance drainage by adding perlite, coarse sand, or pumice. Ensure the pot has drainage holes to prevent water accumulation around the roots.
Temperature and Humidity
The Candelabra Cactus prefers warm, stable indoor temperatures, ranging from 65°F to 85°F (18°C to 29°C). It can tolerate brief temperature drops but should be protected from conditions below 50°F (10°C); it is not frost-hardy. This plant is adapted to dry air and performs well in average household humidity, so no misting is needed. Avoiding cold drafts from windows or air conditioning vents benefits its health.
Fertilization Needs
The Candelabra Cactus has minimal fertilizer needs. During its active growing season in spring and summer, it benefits from infrequent feeding. A balanced liquid fertilizer, diluted to half strength, can be applied once or twice. Over-fertilizing should be avoided, as it can harm the plant with weak, rapid growth. No fertilizer is needed during the dormant winter months.
Potting and Managing Growth
When selecting a pot for the Candelabra Cactus, select one with drainage holes to prevent waterlogging. Terracotta or unglazed ceramic pots are preferred for their porous nature, allowing better airflow and moisture evaporation beneficial for succulents. Initially, a snugly fitting pot is suitable; when repotting, select a container only one size larger.
Repot every two to three years, or when the plant becomes root-bound or top-heavy. The best time is spring or early summer, coinciding with active growth. Handle with care during repotting due to sharp thorns and milky sap. Moisten the soil before removal to loosen the root ball.
This plant can grow tall indoors, reaching 6-9 feet. Pruning can manage shape or size. Use a sharp, sterilized knife for clean cuts. Exercise caution due to irritating sap.
Addressing Common Indoor Problems
Root rot is a frequent issue, manifesting as mushy stems or yellowing foliage. It results from overwatering, where soil remains wet too long. To address root rot, reduce watering frequency and ensure the soil dries completely between waterings. In severe cases, repot into fresh, dry soil, removing affected roots.
Etiolation, characterized by thin, stretched, and leggy growth, indicates insufficient light. Move the plant to a brighter location, such as a south or west-facing window. Etiolated growth cannot revert, but pruning leggy sections encourages compact, healthier new growth.
Spider mites and mealybugs can affect Candelabra Cacti. Spider mites cause a dusty appearance or fine webbing; mealybugs appear as small, white, cotton-like clusters. Treat infestations with insecticidal soap or neem oil. Regular inspection aids early detection and treatment.
Stem rot or soft spots, often from fungal issues due to high humidity or poor air circulation, can occur. If soft spots appear, cut away affected parts with a sterile knife to prevent spread. Improve air circulation and ensure proper watering to prevent these fungal problems.
Safety and Ideal Placement Indoors
The Candelabra Cactus produces a white, milky sap (latex) that can irritate skin and eyes. It is also toxic if ingested, posing a risk to humans and pets. When handling the plant, wear gloves to prevent skin contact. If sap contacts skin or eyes, rinse immediately.
The plant also has sharp thorns. Exercise caution when moving or tending the plant to avoid pokes. Due to the irritating sap and sharp thorns, careful indoor placement is important, especially in homes with children or pets.
Ideal placement is in a bright area, out of reach of children or pets. Given its potential to grow tall, plan for its eventual size. Place it on a sturdy stand or in a heavy pot to prevent toppling as it grows.