How to Care for a Moon Cactus?

If you are a succulent lover, you would definitely want to fall in love with the Moon Cactus. One of the great looking cactus species, they mesmerised you with their bright pink, yellow, or orange colors. One of the excellent means to fill the empty spaces on your office desk or even a window, they are indeed quite easy to care for.

Caring for Moon catus will need not be difficult. You need to ensure that you are watering it properly and sufficiently and providing it enough sunlight. Moon Cactus is a man made cactus and grows from a graft. If you have taken a proper care of the graft, there is nothing you need to worry about it. 

Moon Cactus – An Overview

Moon Cactus belongs to the category of man made cactus. Moon cactus is scientifically known as Gymnocalycium mihanovichii. It is also known by a host of other names that include Ruby Ball, Hibotan Cacti, Red Cap, or Red Hibotan. Native to the dessert regions of South America, such as northeast Argentina, Brazil, Paraguay, and Bolivia, the cactus belongs to the Cactaceae family.

Moon Cactus is a type of grafted variety and comes with an attractive ball-shaped top. The cactus produces the saw-toothed foliage and comes with the white fragrant flowers throughout the summer and fall.

The Moon Cactus is one of the excellent options for various growing scenarios. It can be grown as both indoor and outdoor cactus plants. You can grow it in a potted environment or even on ground. 

The Moon Cactus - A t a Glance
  • Watering – Once every two weeks
  • Sunlight – Bright shade that provides 1 to 2 hours of indirect sunlight
  • Pet friendly? – Yes, not toxic for cats, dogs and humans
  • Size – Smaal, generally one inch in diameter

The luminous colors that these cacti come make them appear as if they are fake. They aren’t fake, but man made. That is the major difference between a fake cactus and a Moon Cactus. 

A few Facts about Moon Cactus
  • The Moon cactus needs a mix of both bright sunlight and a shade. This is because they are created using two different cacti with different needs.
  • They can thrive in the normal room temperature and work with lower humidity levels. It is advisable to keep them indoors to avoid frosting
  • Moon cactus does not need regular watering. You can check moisture levels in the soil before watering.
  • Underwatering can be better than overwatering when it comes to the moon cactus
  • Moon Cactus is slow growing , and thus does not need you to worry about repotting.
  • Moon cactus is not toxic to cats, dogs or humans.

How to Care for a Moon Cactus?

Taking care of Moon Cactus is the same as taking care of all the other perennial cacti. Now that Moon Cactus is not a single cactus, but comes with the two cacti grafted together, they may need a special care.

The moon cactus actually comes with instructions on how to take care of it. Under ideal conditions, the plant does need you to have a temperature on the warmer side. You would need to have a minimum of 48 degrees F temperature for surviving. If you are growing them in the bright light, you will need to partially shield them from the bright sunlight. 

In essence, the moon cactus is a low-maintenance plant and should not necessarily need any specific attention that you need to take care of. 

Some of the important aspects you need to take care of can include 

Soil for Moon cactus

Like most other cacti, Moon Cactus needs a well-draining soil mix. The issue here can be that you need to provide the soil in such a way that the needs of the two plants should be handled. Before potting your cactus, ensure that you have a pot that has a good number of drainage holes.

Water Requirements

The needs of water of a moon cactus can be extremely minimalistic. You need not water it quite often. If you are in an area that receives huge rainfall and is growing it in the outdoor, you will need to take care that you have covered it adequately. You should never overwater it so that pot is waterlogged.  Depending on whether the moon cactus is younger, or older, you should take enough care in how to handle the watering just as you would take care of the other succulents. 

Sunlight and temperature

The temperature requirements of the moon cactus are equivalent to those of any desert plant. They do need bright, but indirect sunlight. Make sure that the plant does not get prolonged periods of bright light. This can severely damage the plant. It can be a good idea to use a covered porch to avoid the direct sunlight. If the temperature drops below 40 degrees C, you can bring the cactus inside the home for a better result.

Avoid Root Rot

One of the major issues that you are likely to come across when taking care of your moon cactus would be the root rot. The prime reason that can cause root rot can be the overwatering. Make sure that you are not overwatering the cactus, in any case, to ensure that an improved performance and growth. The plant is extremely low maintenance and that should make it one of the practical options.


The moon cactus does not need you to provide it with a huge amount of moisture. They would thrive with the relative humidity. However, they would also live healthy in the lower humidity levels. Make sure that the soil is dry before adding any moisture. 

You can mist them quite occasionally. Misting the cactus can provide the much-needed moisture and help it stay healthy without the need to make the soil wet.

A few other tips for taking care of moon cactus would ideally include:

  • Water the soil rather deeply when the soil is dry up to one inch. Watering before that stage can make the root rot. 
  • In winter, it is advisable to avoid watering until the soil has dried out to a depth of about 3 inches. If the cactus has grown older than one year, it would be advisable not to water it at all during the winter. 
  • You can fertilize the moon cactus with 1/4 teaspoon of 15-15-15 water-soluble fertilizer mixed in one gallon of water. Using this fertilizer once every week may be a good idea.
  • If you have opted for fertilizing the plant, do it in place of one watering. 
  • Trim of the excessive amount of foliage from time to time.

What is the Moon Cactus Lifespan?

Under normal circumstances, the Moon Cactus would live for two to three years. The primary reason for their short life is that they do not have chrolophyl which is needed for photosynthesis. However, the grafting technique helps them live for a longer lifespan. 

What is the moon cactus lifespan? How long does the moon cactus live up to? On average, the moon cactus can live up to one to three years. However, there are instances that the moon cactus has lived for more than 5 years. 

While most of the cacti can live for up to 10 to 200 years, the lifespan of the moon cactus can be less than the rest of the cacti. Moon cactus is a grafted cactus and can live for a maximum of five years. Another cause for the shorter lifespan can be due to the rootstock which outgrows the top part o the plant. 

How to Graft Moon Cactus?

Grafting, as you might be aware of, is the horticulture technique where two plants are combined. The purpose of the technique would involve the technique of growing a single plant by using two plants. This will ensure that the final plant will have the qualities of the two plants. 

Grafting requires you to use the scion which is the top plant that is used for fruit production and other ornamental qualities. The part of the plant at the bottom is called rootstock which supports the scion and provides the nutrients from the soil that it requires. In the case of the moon cactus, the Gymnocalycium mihanovichii is the scion and the Hylocereus is the rootstock. 

Follow the steps here below for grafting the moon cactus:

  • For grafting the moon cactus, you should get a new rootstock. While Hylocereus can be one of the practical choices, you may also use Cereus or Trichocereus. The rootstock should be exactly of the same size as the scion. 
  • Make a clean cut on the top of the rootstock
  • Make a corresponding cut of the scion. 
  • Place the scion on the rootstock and align both the plants together. 
  • Use a rubber band to secure both the cacti.

That should complete the grafting process. However, quite easy and simple it may appear, you will find that it is equally difficult if you do not have an expertise in the field. 

Why is Your Moon Cactus Dying and How to Save it?

The moon cactus can die because it has not been destined for living longer. Of course, they do not need much care and maintenance, but the fact remains that they do not live long. In fact, the shorter lifespan of the moon cactus is due to the incompatibility of the two plants used in the grafting process. The prime reason that a moon cactus will die would be due to rootstock for moon cactus that outgrows the top part of the plant. 

In essence, grafted plants should ideally have a longer lifespan, but the combination of the rootstock and scion used in the moon cactus is completely incompatible. The disparity in the growth rate of the two plants makes the rootstock of cactus to grow faster than the scion and this ultimately results in the death of the plant. 

How to save a dying moon cactus? If both the cacti are in good health, you will be able to save them to some extent. As long as the moon cactus has not been overwatered, you can move to save the cactus to some extent. 

The next step would be to follow the options here below:

Save the Rootstock of Cactus

As long as the rootstock and scion are together, there would be no way that rootstock will be able to grow on its own. Removing the scion and letting the rootstock to grow on its own can make the rootstock to grow on its own. 

Here is how you can save the rootstock of cactus: 

  • Get yourself a sharp and clean knife
  • Make a clean cut a little below where the rootstock has been 
  • Make sure that you have removed all the parts of the scion from the rootstock 
  • Place the rootstock in a sunny window 
  • Make sure that you are watering it in the right manner as you should water it.

Save the scion

If you are looking to save the scion, you may do so by grafting it on the rootstock. The video here should ideally give you a clear indication of how to work with regrafting of the scion on the new rootstock. 

The steps for the purpose here can include:

  • Buy a new rootstock 
  • Make a clean cut on the rootstock and remove the top of the cactus. 
  • Take your scion and remove the rootstock of the scion 
  • Make sure that only a circular area of the flesh of the scion is seen and no green is visible. 
  • Place the scion on the rootstock so that the circle of the flesh matches on both the cacti. 
  • Use a rubber band to secure the scion onto the rootstock.

It will take around 8 weeks or so for the grafting to settle down. 

Some Common Problems with Moon Cactus

Even when Moon Cactus is known to grow under any condition, it may have some issues that may need to be addressed –

The color of the moon cactus fades

The Moon Cactus is characterised by its attractive colors. It is possible that you would notice the bright red, yellow and orange color fading away. It can be due a lot of direct sunlight. The direct sunlight can make the cactus to loose its pigments, and thus fade.

Solution – Move the cactus to a shaded place. Moon Cactus should get enough sunlight, but it should be indirect.

Moon cactus begins to callapse

The primary reason for the cactus to collapse is the root rot. Overwatering the main cause for the root rot. Check out if you are overwatering the plant.

Solution – Opt for moderate watering in tuune with the instructions

Upper Ball begins to detach

The Moon cactus is a grafted cactus. The two cacti species can have different growth rates. This can result in the top ball detaching the base.

Solution – Remove the top ball and graft it onto another rootstock

Edges of the scion turn Brown

This can happen due to two reasons – either overwatering or too much of direct sunlight.

Solution – Limit water and move the plant to a shaded place that receives indirect sunlight.

Care against Pests and Diseases

Cactus is normally not affected by pests. However, since Moon Cactus is an indoor cactus, it can be infested with pests. The most common pests that can affect the moon cactus would include spider mites or mealybugs. You can treat them with neem oil, and chemical pesticides. When it comes to the chemical pesticides, you may need to take care to see if the cactus can withstand it.

When it comes to the diseases, the root rot is one of the most common in Moon Cactus. It can be a result of slower drainage or overwatering of the plant. If that happens, you may need to discard the rootstock, and graft the upper portion onto a new cactus.

The Concluding Thoughts 

Moon cactus is indeed one of the most irresistible ornamental cacti ever. The man-made cactus does require a lot of grafted cactus care and needs to be taken care of in a special way. If you are able to simulate a natural environment for them, you will indeed be able to get the best possible experience of the beautiful, colorful and lovely cacti. 

Remember that the moon cactus is a grafted plant and they need to be taken extreme care of. If you take proper care of it, you can be assured that it will grow to greater quality and health for a prolonged period of time. 


Why is the moon cactus top rotting?

The moon cactus top can rot or turn brown if the root of the cactus has begun to rot. The most common reason for the brown or rotting stem can be the issue of root rot. This can result from overwatering and drainage. 

What are the moon cactus benefits? 

The moon cactus can absorb carbon dioxide and can also act as a filter for the environment. The moon cactus has also been rated to be one of the excellent options from the Feng Shui point of view. 

How often do you water a moon cactus?

Wait a week before you water a newly planted cactus. You should water it before at least one-inch deep soil is dry. 

Why is my moon cactus dying?

One of the most common reasons for the moon cactus dying can be the issue of root rot. This can always be the result of overwatering. That can perhaps mean the end of your cactus and the plant is perhaps gone forever.


Nikita is a Succulent lover. She really enjoys planting and nourishing them. She loves to share information about various Succulents on this blog to aware people more about these awesome plants.

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