The Monkey Tail cactus derives its name from its long supple stems that are covered in soft spines that look like strands of white hair. Except for their light green color, the stems look and feel like primate’s appendages.
The plant belongs to the Cactaceae family, a group of perennial succulent plants, most of which originate in the Americas, both north and south.
It is of the genus Cleistocactus and is native to the mountainous regions of Santa Cruz in Bolivia. The stems of the cacti in this genus grow in the form of columns. The name of the genus refers to the ‘closed’ nature of the flowers which seldom open fully.
In the case of the Monkey Tail or species Colademononis, the columns are soft and droopy, rather than standing tall as the typical desert cactus would.
There is a subspecies, ‘Winterii’, which is sometimes referred to as the Golden Rat’s Tail Cactus.
The Monkey Tail is classified as a Lithophyte, as it has shallow roots and grows naturally among stones and in the crevices of cliffs, surviving off the moisture in the atmosphere.
In order for your Monkey Tail Cactus to thrive in its adopted home, there are several ways in which you can help it.
Monkey Tail Cactus Care
In a nutshell, the plant requires soil that is well-drained and slightly acidic. A layer of mulch will prevent the shallow root system from being exposed to extreme temperatures. It would prefer a warm climate but can survive in sub-freezing temperatures as low as those found in Zone 9. The Monkey Tail Cactus has definite seasonal variances with regard to water, light and humidity. The plant adjusts its growth and dormancy according to the available light. In summer, it requires 10-14 hours of bright, but not searing, light. Water should be withheld in winter and applied whenever the soil dries out in the other seasons. High humidity levels, in confined spaces, are problematic in cold and warm temperatures.
We will explore each of these in more depth below.
As the Monkey Tail derives much of its moisture and nutrients from the atmosphere, it does not develop a robust root system. It does not require much from the soil, beyond providing an anchor strong enough to support the weight of the hanging tails.
Cacti prefer to grow in soil that is acidic or near neutral. The Monkey Tail grows best in soil that has a pH level ranging from 5.5 to 6.5.
When watering, take care that the pH level of the water supports the long term needs of your Monkey Tail. Alkaline water will slowly alter the soil, over time, which will make it an unsustainable growing medium for the plant.
It is vitally important that the soil drains well between watering. Cactus plants, in general, do not enjoy having their roots wet for long periods of time. A generic cactus soil mix that drains well will be ideal.
The shallow roots of the plant enable it to quickly absorb any water that falls on the soil. However, the roots are exposed to surface temperatures. Care must be taken to protect them from extreme heat and cold by adding a layer of mulch over the soil to act as an insulator.
This mulch can be in the form of bark, vermiculite, or any other inert substance that will not break down and change the pH level of the soil, causing it to become alkaline.
Cacti can tolerate strong light levels and the Monkey Tail is no exception. Their annual growth cycles are determined by light levels. They will respond to an increase in natural light in spring by kicking off a growth spurt.
Light will also activate the reproductive cycle. Buds will appear in spring and the plant will bloom through most of spring and summer. This is an opportune time to propagate the plant through pollination.
Generally, the lighter green your cactus is, the more light it would appreciate. The Monkey Tail is a yellowish-green color and will do well with between 10-14 hours of direct sunlight.
If possible, place it in or near the rays coming from the direction of the equator, i.e. a south-facing window in the northern hemisphere and vice versa.
Similarly, the lowering of the light levels in fall (autumn) and winter will slow the plant down until it reaches a point of dormancy. This is a vital rest period and should not cause concern.
Your Monkey Tail would probably thrive outdoors in a sunny spot where the other elements of nature can be controlled.
However, if the area you live in has high rainfall in summer or is prone to unpredictable temperature fluctuations or frost, it is best to keep it in a managed environment, indoors.
Watering, much like the light levels it is exposed to, affects the growth of the Monkey Tail. Care needs to be taken to keep these synchronized.
Always water deeply and let the soil dry out completely before watering the plant again. Shallow watering will encourage the roots to grow towards the surface, causing them to have less of a hold on the soil.
During winter, the plant only needs enough water to sustain it in its dormant state. Deep watering, every 6-8 weeks should suffice.
As spring approaches, slowly increase the frequency of the watering. The roots will absorb as much as the plant needs. Ensure that the rest of the water drains away.
The increased temperature and light levels in summer will dictate how often the soil dries out. Be responsive to this as you will be watering more often in this season.
Before repotting your plant, ensure that the soil has dried out completely.
The Monkey Tail Cactus prefers a warm climate, however, it can survive in Zone 9, and tolerate temperatures as low as -6° Celcius or 20° Fahrenheit. If you live in such a cold climate, it is best to allow the plant to spend the winter indoors.
If the plant is exposed to such low temperatures it becomes imperative that it is not watered. Cacti survive by storing moisture in their stems. If this water freezes, it will damage the cells of the plant.
Try not to make sudden changes to any of the elements of the plant’s environment, e.g. light or temperature. This could give the plant a systemic shock from which it may not recover.
The natural environment of the Monkey Tail is high up, above the jungle, clinging to the cliffs in Santa Cruz, Bolivia. It can tolerate a fair degree of moisture in this atmosphere.
In an indoor setting, the humidity levels to which the plant is exposed, need to be controlled along with its lighting, temperature, and watering levels. In summer, when it is hot, the plant will use the moisture in the atmosphere to spur on its growth.
However, in winter, too much humidity, like too much water on its roots, will have the effect of overwatering the plant and will cause its cells to become waterlogged and to decay.
In a closed environment with poor circulation, excess humidity creates the ideal environment for mold to grow. This fungus thrives on decaying organic matter.
Regularly examine your plants for signs of mold, as it can be detrimental to the health of humans.
Cactus plants have evolved over millennia in order to adapt to their environments. As with watering, they do not need much fertilizing. Once a season, during spring, summer and fall, should be sufficient.
In spring and summer, low nitrogen or foliar feed component is needed, along with a significant amount of phosphorous, in order to stimulate the development of flowers, seeds, and fruit. Potassium is also required to strengthen the stems and build the health of the plant overall.
The ratio of nitrogen: phosphorous: potassium should be 5:10:5.
A slow-release fertilizer is advisable so as not to shock the plant. Each application should last a season.
The main attraction of the Monkey Tail Cactus is its tails. Therefore, it will look best in a hanging basket or on a raised pedestal which shows off this unique feature.
It is also a tactile plant. The spines grow into long soft ‘hairs’, soft enough to stroke. At the base of the stem, they tend to be ginger, becoming much lighter towards the tips of the stems.
The stems are ridged in order to allow for expansion and contraction, depending on the water available. They do not have leaves but rather have spines protruding from aerioles or nodes.
Unlike most other plants, where chlorophyll is found in the leaves, this food-producing substance is found in the stems of cacti. The stems are yellowish-green in color.
The Monkey Tail is a relatively fast-growing cactus. In spring and summer, the stems or ‘tails’ can grow up to 10 cm per month. When mature, the stems can reach 7.5 centimeters in diameter, and grow as long as 2.5 meters long.
The stems are rigid for a few feet at the base and then start their characteristic droop. There can be up to three to five stems on one plant, branching at the base.
You can add to this number and create the appearance of an ‘octopus’, by growing several plants in the same pot.
A medium-sized pot with several tails cascading will certainly create a talking point. Even more striking would be a Monkey Tail grafted onto an upright cactus of the same genus.
During spring and summer, the plant puts forth large pink and red flowers and a range of hues in between. The flowers can appear anywhere on the stems.
The principal way of propagating a Monkey Tail Cactus is to lop a piece off the end of a tail, leave it to dry, and then plant it about a centimeter deep in dry soil. It could take a month to take root and start growing a new plant.
The end of the tail that has been cut will invariably grow branches or ‘pups’, which will look remarkably like fingers. These pups can be twisted off and propagated in the same way as cuttings.
Pollinating flowers takes patience and expertise but you will be rewarded with fruit and ultimately seeds that can be planted. This is a way of creating hybrids within the species.
The Monkey Tail does not require much depth as the roots are shallow. The width of the pot will be determined by the number of plants you choose to put in it.
It is recommended that you repot the plant every three years to replenish the soil. It will not be necessary to increase the size of the pot unless you are thinking of increasing the number of individual plants in it.
Ensure that the soil is completely dry before repotting the plant.
Common problems with the Monkey Tail Cactus
Most of the Monkey Tail’s problems are caused by overwatering, watering out of season, or too much humidity in the atmosphere. Overwatering will lead to discoloration of the stem and ultimately decay. It will also cause the roots to rot.
Too much humidity will similarly cause parts of the stem to rot and gives rise to mold which thrives on decaying matter.
Several pests can thrive undetected in between the hairs of the Monkey Tail Cactus. Mealybugs are tiny light grey, oval insects. They have the appearance of being powdery and can be mistaken for mildew. They cannot fly but seem to suddenly invade a plant and breed rapidly.
These parasites favor succulents. They suck the sap out of the plant and secrete honeydew, a sticky substance that attracts ants, as well as bacteria and fungi.
The plant should be quarantined until the pests have been eradicated. Mealybugs can be removed with a spray of water under pressure. Take care not to drown the cactus in the process.
Spider mites are very small reddish-brown pests that are very difficult to detect until they have caused actual damage to the plant.
They colonize the undersides of leaves, creating white web-like structures. The damage they cause appears in the form of numerous brown patches.
Infected leaves should be pruned. As with mealybug, the plant should be isolated and sprayed with water under pressure. This may need several applications.
If applying an insecticide, ensure that the substance is targeted specifically at spider mites and will not be detrimental to their natural predators, such as ladybugs. A longer-term solution would be to introduce these natural predators to the environment.
The scale is another insect that produces honeydew. This sticky substance attracts ants which provides protection for the scale. The presence of ants should be a trigger to look for scale and mealybugs.
Scales have an exoskeleton that is impervious to insecticides. They need to be eradicated with rubbing alcohol applied directly to their chosen habitat.
Frequently asked questions about the Monkey Tail Cactus
Is the Monkey Tail poisonous?
The flesh of the plant is toxic to humans and animals. However, the hairs can cause pain when pressed too hard. This could deter children and pets from tasting them. It would be best to keep the plant out of reach of both.
Is the Monkey Tail invasive?
It does propagate of its own accord when pieces of the plant fall off. In an environment conducive to its growth requirements, it will spread. If you live in the ideal environment for natural propagation, you might think of growing it in a contained setting.
The Monkey Tail Cactus is an attractive plant that is easy to grow and propagate. It does not need a great deal of maintenance. Sensitivity to its basic needs and annual rhythms will keep it healthy and provide a talking point for many years.
Marcel runs the place around here. He has a deep passion for houseplants & gardening and is constantly on the lookout for yet another special plant to add to his arsenal of houseplants, succulents & cacti.
Marcel is also the founder of Iseli International Commerce, a sole proprietorship company that publishes a variety of websites and online magazines.