The Euphorbia trigona, often called the African Milk Tree or Cathedral Cactus, is a striking, low-maintenance succulent prized for its upright, branching, candelabra-like growth habit. Propagating this plant from stem cuttings is a simple and effective method for increasing your collection. The process requires careful handling and preparation to ensure the new cutting successfully develops roots.
Essential Safety and Preparation
The most important consideration when handling Euphorbia trigona is the white, sticky sap, known as latex, which the plant exudes when cut. This latex is toxic and a severe irritant to skin and eyes. Contact with the sap can cause skin irritation, rashes, and blistering, and if it enters the eyes, it can lead to temporary vision impairment. Because of this caustic sap, you must wear thick garden gloves and, ideally, eye protection before making any cuts. Gather a sharp, sterilized knife or razor blade to ensure a clean cut, along with paper towels and a well-draining succulent potting mix.
Taking and Callousing the Cuttings
Begin by selecting a healthy, actively growing side branch from the parent plant, aiming for a segment that is at least four to six inches long. Use your sterilized cutting tool to make a clean, swift cut at a joint or near the main stem. A clean incision promotes faster healing for both the parent plant and the cutting.
Once the cut is made, the milky latex sap will immediately begin to flow. Stop this flow quickly by blotting the cut ends with a paper towel or by rinsing them under cool, running water for about 30 seconds. This action prevents excessive sap loss and cleans the wound.
The newly cut segment requires a period of callousing, which is the most important step for successful propagation. Place the cutting in a dry, shaded, and warm location, allowing the cut end to sit undisturbed until a hard, dry scab, or callus, forms. This process can take anywhere from three to seven days, depending on the humidity and temperature. Planting before a callus forms almost guarantees that the cutting will rot.
Planting and Establishing the New Plant
After the cut surface has completely dried and sealed over, the cutting is ready to be potted in an appropriate medium. Select a small container with ample drainage holes and fill it with a specialized succulent or cactus potting mix that contains materials like perlite or sand to enhance drainage. This highly porous substrate is necessary to prevent water retention and stem rot.
While optional, dipping the calloused end into rooting hormone powder can help stimulate root formation. Insert the prepared cutting just deep enough into the soil mix to keep it standing upright and stable. You may need to use small stakes or lean the cutting against the pot’s edge if it is particularly tall.
Place the newly planted cutting in an area that receives bright, indirect light, as direct, intense sun can stress the unrooted segment. The rooting process typically takes approximately four to eight weeks. Avoid watering the cutting immediately after planting; instead, withhold water for seven to ten days to prevent fungal issues.
After the initial dry period, water the soil lightly, ensuring it dries out completely between subsequent waterings. You can check for root development by gently tugging on the cutting; if it offers resistance, roots have begun to anchor it in the soil. Once new growth appears on the stem, the plant is considered established and can be cared for as a mature Euphorbia trigona.