🌵 The Architectural African Milk Tree (Euphorbia trigona)

The African Milk Tree is a very popular indoor plant, admired for its incredibly striking, vertical growth that gives it an immediate architectural quality. It is widely known by its common name, the African Milk Tree, and is often mistaken for a true cactus due to its ribbed structure and spines.

Foliage and Form

The plant's distinctive appearance comes from its robust, sharp, vertical lines and ribbed branches that are a vibrant green color. Along these ribs, it produces small, fleshy, tear-drop-shaped leaves, usually along the edges, which give it a unique look. As an indoor houseplant, it is considered evergreen and retains its striking shape year-round.

Flowering and Scent

While the African Milk Tree can technically flower in nature, it rarely flowers indoors. When it does, the flowers are small and inconspicuous. The plant is not fragrant; its appeal is purely visual and structural.

Height and Spines

The plant currently stands at a convenient height of about 40 cm (16 inches), making it ideal for tabletops or desks. However, this succulent is known for its vertical growth and can become quite large, potentially reaching 6 to 8 feet (up to 2.5 meters) or more indoors over many years, maintaining its unique, tree-like structure. It is definitely a plant that has spines along the edges of its ribs.

Care and Requirements

This plant is highly valued for its minimal care requirements and resilience, making it an excellent choice for any home or office. It is recommended for spots with partial shade, thriving best in bright, indirect light. The description also notes it performs well in half-shadow, which shows its versatility in bright indoor spaces. To support its growth, it should be potted in well-draining soil, such as a mix specifically designed for cacti or succulents.

Watering

As a succulent native to Central Africa (including Cameroon and Gabon), it is adapted to arid environments. It prefers to be watered only every 8–10 days, and it is crucial to ensure the soil is completely dry between waterings to prevent root rot. During the main growing season (spring to early fall), fertilize it monthly using a balanced, water-soluble fertilizer.

Note: The African Milk Tree, like other Euphorbia species, produces a white, milky sap (latex) when cut or damaged. This sap is considered toxic. It is an irritant that can cause skin and eye irritation and is toxic to both humans and pets (cats and dogs) if ingested. Always handle the plant with care, especially when pruning, and keep it out of the reach of children and animals.