As far as I remember (which is not very far at the moment) my first houseplants were cacti. As a child I was fascinated by their odd shapes, colors, and spines. Unfortunately I didn’t understand that their water requirements were a bit different than the normal houseplant, and in my zeal for taking care of them I overwatered and killed them. I moved away from them as plants towards ones I had a bit more success taking care of, namely African violets. Until this past May I hadn’t had a cactus since I was a child. May was when this little guy came into my life.
My little sister called me one day and told me that, in the end of year rush to move out and get rid of things, someone had planted a cactus in the community garden, and asked if I wanted it. While some cacti do well in South Florida, this one was clearly meant to be an indoor plant. Even though I didn’t know what type of cactus it was I decided what the heck, and said I’d take it. She brought me this cute little grafted cactus, which I repotted it in a broken mug. It had been living happily (I hope) in my window ever since.
Grafted Cacti are commonly found in grocery stores and home improvement stores, and are popular as houseplants. While most people think that the colorful top is a flower, it’s actually a different type of cactus than the bottom portion. The top portion is Gymnocalycium mihanovichii friedrichii, or as it is commonly know, a moon cactus. This variety of cactus comes in a range of bright eye-catching colors, but does not produce chlorophyll so it cannot make its own food like a normal plant. The moon cacti cannot live for more than a few weeks by themselves, so they are grafted onto a different species of cactus, which has chlorophyll, so it can survive.
In order to graft cacti together, the tops of both cacti are cut off with a sharp knife. The desired top is placed on the desired bottom and held together by rubber bands until the junction has healed. More detailed instructions for how to graft cacti can be found here. Grafting is a technique also used in fruit and flower propagation.
As young me found out, caring for a grafted cactus is a bit different than caring for other houseplants. The most noticeable difference is the water requirements, but there are other differences as well.
Water Requirements: The general rule of thumb that I’ve come across over and over again with regards to cacti is “When you water, water well”. It is important to let cacti dry out between waterings or you risk drowning it.
Soil Requirements: Grafted cacti grow well in any succulent mix, high quality planter mix, or humus.
Light Requirements: Light shade is the perfect amount of light for grafted cacti.
Temperature Requirements: Grafted cacti should be kept in a room that is above 60°F (15°C). Temperatures over 100°F (38°C) can also be damaging to cacti.
Nutrient Requirements: It is a good idea to fertilize your grafted cactus monthly between April and September (growing season). Standard houseplant fertilizer that has been diluted can be used, but take care not to over fertilize the cactus or it may lose its shape.
Pruning: If any side branches grow from the green base, cut them off as they are trying to bypass the moon cactus on top. There is no need to cut off the side branches from the moon cactus.
Grafted cacti typically only live a few years, don’t take up a lot of space, and don’t require a lot of care making them great for anyone who wants a houseplant without the hassle that larger, more involved plants can bring. Because they do not typically grow any larger than they are when you bring them home, grafted cacti are also great plants for small spaces like apartments and dorm rooms, but their texture, color, and personality make them great additions to any houseplant collection.
Cactus Collection: Grafted Cacti – Information about the moon cactus, the base cactus varieties, and the grafted cacti.
Cactus Collection: General Care – General care instructions for cacti.
SFGate Red Top Cactus Care – General care instructions for Grafted cacti.
UCC’s biology department plant of the week: Grafted Cacti – Good general information and instructions on how to graft cacti.