Gymnocalycium mihanovichii 'Variegata'

Gymnocalycium mihanovichii is a species of cactus from South America. The most popular cultivars are varied mutants which completely lack chlorophyll, exposing the pink, red, orange, or yellow pigmentation; coming from the betalains in the plant becoming exposed. These mutants, which normally would be unable to survive for even a few days, are often grafted onto a Hylocereus cactus, and the combined plant is called a "moon cactus". Hylocereus is practically an arbitrary choice, as its only purpose in the graft is to provide nutrients for the mutated plant above it. Trichocereus or Cereus can also be used.

“Moon cacti” are commonly grown as houseplants. Unfortunately however, most “moon cacti” do not survive for very long due to drastic differences between the growth rate and size; the Gymnocalycium usually maxes out at around a few inches, meanwhile the Hylocereus grows much larger.