African milk tree should not be rooted in water or it will rot. To propagate this plant, you can take a 5-inch stem cutting in late spring or early summer. The timing is important. The plant is in more active growth at this time and the long daylight hours and dry warmth support faster rooting. The most successful cuttings come from newer growth rather than older, thicker stems.

Protect your skin and eyes when making cuttings, as the sap can cause serious irritation or an allergic reaction. Stopping the flow of milky sap is important to the health of the parent plant and the cutting. Dip the cutting end in water and spray the parent's wound with water. Then let the cutting dry out ("callus") in a warm, dry space before planting. This plant can take a month or more to callus because the stem is so thick. 

Prepare a pot of moistened potting mixture, with added perlite for better drainage (or a cactus and succulent potting mix without added fertilizer), and a layer of horticultural sand or vermiculite on top to prevent rot. Insert your cutting into the potting mix and place it in filtered light at a room temperature of about 70 degrees. If nights are colder in your home (below 60 degrees), a heated propagating mat can be used to accurately control temperature.

Keep the potting mixture just barely moist for two to six months. At that point roots will have formed.  Once new growth appears on the cutting, you can repot the plant in succulent potting mixture and treat the plant as a mature euphorbia.

For more information on caring for this plant see our Guide to African Milk Tree.
- Courtesy of NYBG Plant Information Service