Q: I know this is kind of a stretch, but IΒ got your email off an answeredΒ question about caring for a cactus on a website.Β I bought a cactus in Japan (I'mΒ stationed over here) and I have a couple questions. First is it normal to have that discoloration around the base and arms?Β Also, what kind of cactus is this? I just want toΒ makeΒ sureΒ I'm doing everything for it so it can survive!
A: Your plant is a type of Euphorbia. These plants are in the Euphorbiaceae family rather than the cactus family Cactaceae. They are often confused for cacti due to the spines and general appearance. The browning is a function of age and not anything wrong with the plant. Β Caring for this plant is similar to what you would do for cacti. Make sure it is in well-drained soil and water once a month if kept indoors in a container. The hot desert sun would be too much and I would recommend indirect sunlight, but in other locations where itβs not so hot make sure it gets plenty of sun. A water-soluble complete fertilizer can be used at a quarter strength monthly during the growing season. Avoid fertilizers that are high in nitrogen.
Peter L. Warren is the urban horticulture agent for the Pima County Cooperative Extension and the University of Arizona. Β Questions may be emailed to tucsongardensage@gmail.com.
