Off with your head! Cactus propagation is commonly done by grafting, a process where a cut piece of one species is grown onto a wounded piece of another. Grafting cactus plants is a straightforward method of propagation which even a novice gardener can try. Different species work better with different methods, but a brief cactus grafting guide follows with basic instructions on how to graft a cactus.
Cacti comprise some of my favorite plants due to their uniqueness of form and unusual characteristics. Propagation is done through grafting, stem cuttings, leaf cuttings, seed or offsets. Growing cactus from seed is a long process, as germination may be unreliable and growth is at a snail’s pace. Broadly, cacti that do not produce offsets can be propagated by grafting as long as there is a compatible rootstock. The grafted part is called a scion and the base or rooted part is the rootstock.
Cactus Grafting Guide
Cacti are grafted for a variety of reasons. One may simply be to produce a different species mechanically, but the process also produces disease-free stems, to provide a new stem for an existing stem that is rotting or to enhance photosynthesis in plants that lack the ability. Grafting cactus plants is also done to create unique forms, such as weeping plants.
Grafting is common in fruiting plants because it increases the maturity of an existing cultivar for earlier fruit production. The scion becomes the top part of the plant with all the originating species’ characteristics. The rootstock becomes the roots and base of the plant. The union is at the vascular cambium where the wounds of scion and rootstock are sealed together to heal and join.
Once the joining wounds have healed, no special grafted cactus care is required. Simply grow it as you would any other plant.
Rootstock Cactus for Grafting
The generally approved rootstocks for grafting cactus are:
- Hylocereus trigonus or undatus
- Cereus peruvianus
- Trichocereus spachianus
Also, if the rootstock and scion are in the same species, the compatibility is excellent. Compatibility decreases as the family relationship decreases. Two plants in the same genus may possibly graft, but two in the same genera are rare, and two in the same family are very rare. The appropriate cactus for grafting are, therefore, the ones in the same species and with as close a relationship as possible for the best outcome.
How to Graft Cactus
Use very clean, sterile instruments when making cuts. Choose healthy plants and prepare a scion. Cut off the top or at least a 1-inch (2.5 cm.) stem. Then prepare the rootstock by beheading a cactus to within a few inches (7.5 cm.) of the soil.
Set the scion on top of the cut portion of the still rooted rootstock so both vascular cambium are situated together. Use rubber bands to hold the pieces joined as one.
Grafted cactus care is the same as ungrafted cactus. Watch for any insects or rot at the union. In about two months, you can remove the rubber bands and the union should be sealed.