Gymnocalycium mihanovichii friedrichii is commonly known as 'Hibotan' or Moon Cactus. This variant occurs when the plant lacks chlorophyll, and the body color manifests as beautiful pink, orange, yellow, or red rather than the typical green. The Gymnocalycium cultivar -- sometimes called ruby ball cactus or moon cactus -- is actually two cacti in one.A pure red cactus seedling lacks the ability to produce chlorophyll and will die unless it is grafted onto a green one.The green feeds its mutant mate sugar molecules produced from water and carbon dioxide.
The moon cactus (Gymnocalycium mihanovichii var. friedrichii or Hibotan) is prized for its colors. The plant is without chlorophyll, which means that instead of having a green body, it appears red, orange or pink. This also means it can't produce food, so to survive, it must be grafted onto the stem of another cactus. Bacterial infections or other fungal infections may also be causing the stem of your moon cactus to turn brown. In general, if the brown part is soft and mushy, and it covers most of the stem, your plant is probably beyond saving. Your best bet is to discard it and start over with a new, healthy plant. Intro: The popular moon cactus plant is a small grafted cactus. Grafting, which can be done with many plants, is a propagation technique in which a gardener will take two separate plant species, cut them and grow them together as one plant. The plants, if they are compatible, will bond and grow as one. The top cactus of the moon cactus has a mutation that causes it to lack the chlorophyll that makes the cactus green. This mutation exposes the red, orange or yellow color beneath. Cactus that lack chlorophyll cannot live on their own – they die as seedlings unless grafted onto another cactus with chlorophyll. Moon cactus plants are known as Gymnocalycium mihanovichii or Hibotan cactus. Strangely, the plant is something of a mutant and lacks the ability to produce chlorophyll, which means they must be grafted onto a rootstock with that ability. The moon cactus prefers to have a crowded home, which means you can repot in the same pot for several years. In rare cases, and when care of moon cactus is optimum, you may be rewarded with small red to pink flowers in late spring to early summer. Answers. Best Answer: What you have is most likely a grafted cactus. It is actually two different cacti that have been joined together (the bulbous top and spined bottom came off of different cacti originally). A common name for these grafteds is Moon Cactus.  A moon cactus, or 'grafted cactus' is a cactus grafted on to another to grow as one. The top cactus is usually drained of it's chloryphll and cannot create it's own food, thus it uses the bottom cactus. The life spans of moon cacti are very short lived, but they're very pretty. Moon cactus like sunlight, but not direct sunlight-for that will give them sun burn marks and can kill them. A few hours a day (4-6) of sunlight is good. Scientific Name: The two cactus species most commonly used for moon cactus are Gymnocalycium mihanovichii as the top cactus and Hylocereus spp. as the base. Plant Type: Grafted cactus. Light: The moon cactus plant requires bright indirect sunlight. The top cactus of the moon cactus has a mutation that causes it to lack the chlorophyll that makes the cactus green. This mutation exposes the red, orange or yellow color beneath. Cactus that lack chlorophyll cannot live on their own – they die as seedlings unless grafted onto another cactus with chlorophyll. Its Latin name is Gymnocalycium mihanovichii, and it has several common names such as ruby ball cactus or Hibotan. The moon cactus itself is a mutant that lacks the chlorophyll necessary for a plant to feed itself via the process of photosynthesis, or converting sunlight to energy. This species is, therefore, typically grafted on top of another type of cactus from which it feeds. It is common for people to confuse a moon cactus with a cactus flower. Depending on the type of base cactus chosen, a moon cactus might not grow much taller than 12 inches (30.5 cm). While several kinds of cacti live for up to several decades, the Hibotan has a relatively short life span. These grafted cacti -- occurring in yellow and white as well as red -- typically live only a few years and do not grow appreciably. The Gymnocalycium cultivar -- sometimes called ruby ball cactus or moon cactus -- is actually two cacti in one. A pure red cactus seedling lacks the ability to produce chlorophyll and will die unless it is grafted onto a green one. The green feeds its mutant mate sugar molecules produced from water and carbon dioxide show more I have a Moon cactus (also called a grafted cactus) where it has the green stem and a bright colored bulb on the top. I've had the Cactus for about a year now, and much like my other Cacti, it has been doing very well being by the window. However, just last week the right bulb portion started rotting for... Grafted Cactus. Gymnocalycium mihanovichii friedrichii is commonly known as 'Hibotan' or Moon Cactus. This variant occurs when the plant lacks chlorophyll, and the body color manifests as beautiful pink, orange, yellow, or red rather than the typical green. 
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why is it called a moon cactus