The tropical cactus Pereskiopsis spathulata is a favorite rootstock for grafting slow-growing cacti. The rapid-growing Pereskiopsis looks like a bush with thick leaves and spines on its thin branches. Small cacti scions often outgrow Pereskiopsis and have to be regrafted onto larger rootstock.
Benefits of Pereskiopsis
Small, slow-growing cacti do especially well when grafted onto Pereskiopsis rootstock. Pereskipsis grows rapidly and receives water without developing root rot. Left alone, it can grow 8 feet tall in six months.
About Cambium Tissue
When you cut a cactus, you will notice a circle or ring inside. These rings are the cambium tissue, commonly called water pipes. The water pipes of your scion (the cactus that you are grafting onto the Pereskiopsis) should overlap with the water pipes of your rootstock (the Pereskiopsis). This is necessary so your scion will share the moisture transported by the rootstock and grow vigorously. Pereskipsis has more efficient cambrium tissue than most cacti; that is why it grows rapidly and is useful as a rootstock.
Basics of the Cut
Use alcohol to clean your knife and before you begin grafting. This is to kill mold spores.
Cut the seedling to be grafted where it is widest.
Dry cuts can result in grafting failure. The Pereskiopsis that you use for a rootstock should be healthy and juicy. Cut the Pereskipsis where it is a little wider than your scion. Cut a thin slice and leave it on top of the cut to keep the grafting surface moist.
Attaching the Scion
Remove the slice on the rootstock and move the scion onto the moist top of the rootstock. Press the scion down to remove any air bubbles. They should stick together without being weighed down.
Starting the Scion
The rootstock and grafted scion will do best inside a humid container. A 20 L plastic soft drink container with the bottom cut off will accommodate a 6-inch rootstock in a 4-inch pot. You can also use aquariums or plastic bags. A grafted scion can grow into a grown, flowering cacti in six to seven months
Seeds of Pereskipsis are not ordinarily available from garden supply centers, but if you cut off the point of a growing plant; it will form four or five shoots. A cutting will form roots in seven to 10 days and be ready to accept scions in about three weeks.
Pereskiopsis is a tropical cactus. It likes good soil and warm weather, although it can withstand temperature dips to 50 degrees F (10 degrees C) in the winter.