The String of Dolphins (Senecio peregrinus or Curio × peregrinus) is a fascinating succulent prized for its unique foliage. This hybrid features plump, curved leaves that strikingly resemble tiny leaping dolphins. Because of its distinctive appearance and trailing habit, many gardeners seek to multiply their collection. Understanding the most effective and reliable propagation methods is the first step in successfully expanding this delightful succulent.
Addressing Leaf Propagation: Why It’s Unreliable
While many common succulents can be easily propagated from a single leaf, the String of Dolphins is a notable exception. The dolphin-shaped leaves typically lack the necessary meristematic tissue, the specialized growth point required to generate a new stem. If a leaf is removed and placed on soil, it may root and remain green, but it frequently fails to produce the aerial growth needed to form a new trailing vine.
This phenomenon is sometimes referred to as a “living leaf,” where the leaf sustains itself but never progresses into a full, independent plant. Attempting to propagate from a leaf is highly unreliable and significantly slower than other methods. Gardeners should avoid this technique in favor of the plant’s proven and more robust method of reproduction.
Effective Method: Propagating via Stem Cuttings
The recommended and most consistently successful technique for multiplying the String of Dolphins is using stem cuttings. This process ensures the cutting includes the necessary growth points to form a new, complete plant. Select a healthy, robust stem section that is typically three to five inches long, which provides enough material to establish strong roots.
Before making the cut, sterilize your cutting tool, such as a sharp knife or shears, using rubbing alcohol to prevent the introduction of pathogens. Make a clean cut just below a node, the small bump where a leaf emerges from the stem. These nodes contain the cells that will develop into new roots. After separating the cutting, carefully remove the dolphin leaves from the bottom inch or two of the stem to expose two or three nodes.
The next step is allowing the cut end to form a protective layer called a callus. This involves letting the cutting air-dry for two to three days until the wound is completely sealed and dry to the touch. Callousing is a defense mechanism that prevents the cutting from absorbing too much water when planted, which is a common cause of rot in succulents. Once the callus has formed, the cutting is ready to be placed into a rooting medium.
Essential Environmental Care for New Cuttings
Successful rooting relies on providing the correct environment for the calloused cutting. The planting medium must be extremely well-draining to prevent water retention around the delicate new roots. A pre-mixed commercial succulent or cactus soil is suitable, or you can create your own by combining standard potting soil with inorganic amendments like perlite, pumice, or coarse sand in a ratio that promotes rapid drainage.
The cutting should be inserted into the soil just deep enough to bury the exposed nodes, which are the sites of future root growth. After planting, the new cutting requires bright, indirect light to encourage root development without scorching the tender foliage. Placing the pot in a location that receives several hours of diffused light, such as a few feet back from a south-facing window, is ideal.
Unlike mature plants, newly planted cuttings benefit from the soil being kept lightly and consistently moist during the initial rooting phase. This moisture level is important to encourage the new roots to form without becoming waterlogged. Instead of deep watering, lightly mist the surface of the soil near the stem every few days, or water sparingly when the top layer of soil feels dry.
Root development typically begins within a few weeks. You can test for success by gently tugging on the cutting. If you feel slight resistance, it is a sign that the new roots have anchored themselves in the soil. Once established, transition the new plant to a mature watering schedule, allowing the soil to dry out fully between deep waterings to maintain the plant’s health and prevent root rot.