Yes, cactus can propagate in water. While soil propagation is more common, growing cactus in water is indeed possible, though it requires a different approach compared to rooting other types of houseplants.
Understanding Water Propagation for Cacti
Propagating cacti using water involves encouraging cuttings to root while submerged in water. However, a critical first step is necessary before placing the cutting in water. As highlighted in the reference, cactuses can also be grown in water but the technique is distinct and takes longer than for many other plants.
Key Difference: The Scarring Process
Unlike many soft-stemmed plants that can be placed directly into water after cutting, cactus cuttings need time to heal. The cut surface is prone to rot if immediately exposed to moisture. Therefore, a crucial step is allowing the cut end to dry out and form a callus or "scar".
- Why Scar? This drying process seals the wound, preventing rot and allowing the cutting to safely transition to a water environment for rooting.
- How Long? You have to wait for at least a week or more (depending on the weather) for the cut side to be completely dry and scar, before proceeding to next steps. Warmer, drier conditions typically speed up this scarring process.
The Propagation Steps (Based on Reference)
- Take a Cutting: Carefully take a clean cut from a healthy parent cactus.
- Scar the Cutting: Lay the cutting aside in a dry place away from direct sunlight. Wait for the cut end to completely dry and form a hard callus. This takes at least a week, sometimes longer, depending on temperature and humidity.
- Place in Water: Once the cut is thoroughly scarred, place the callused end just above or lightly touching the surface of water in a clean container. You can use a small piece of plastic wrap or a clip to suspend the cutting so only the very bottom is in contact with the water or air just above it.
- Wait for Roots: Place the container in bright, indirect light. Change the water periodically (every week or two) to keep it fresh. Watch for roots to begin forming from the callused end. This process can take several weeks or even months.
Once a healthy root system has developed in the water, the cactus can then be carefully transplanted into a well-draining soil mix suitable for cacti.
Water propagation offers an alternative method for increasing your cactus collection, requiring patience and attention to the essential scarring phase.
