Red Moon Cactus
The colourful moon cactus is a grafted specimen which means it’s two plants joined together!
The colorful top (the scion) is Gymnocalycium mihanovichii. The lower green cactus is a Hylocereus cactus. It becomes known as a moon cactus when the plants are joined. The main job of the lower cactus is to display the Gymnocalycium at an advantageous height!