The fishbone cactus, or Disocactus anguliger, is a tropical succulent that is native to Mexico.
This cactus gets its name from the unique shape of its stems, which grow in an angular or zigzag pattern, resembling a fishbone.
Unlike most cacti, the fishbone cactus loves growing in humid conditions and is completely fine with indirect sunlight. It is also epiphytic, meaning it normally grows on the trunks and branches of large trees in its natural habitat. This makes it a perfect plant to display in hanging containers.
If you are a cactus-lover but live in a place where the climate is not conducive for most desert cacti, then the fishbone cactus is the perfect choice for you.
Like most plants, however, this one comes with its share of potential problems, one of the most common being when the plant becomes wrinkled. The possible causes of a wrinkled fishbone cactus are underwatering, overwatering, low temperatures and excessive sun exposure.
In this article, we will discuss each of these possible causes and what you can do to resolve the problem. Read on to learn more!
Why is my fishbone cactus wrinkled?
Underwatering
If your fishbone cactus is not getting the water that it needs on a regular basis, it will become wrinkled due to underwatering.
Because it is a cactus, most people assume that it requires water as infrequently as desert cacti do, but this is not the case for this tropical succulent. True, it might not need as much water as regular tropical houseplants, but it does need more water than most cacti and other succulents.
Because, like all succulents, it can store water in its body, the fishbone cactus can survive for several weeks if you neglect to water it, but once its water stores are depleted and its soil has dried out, it will become dehydrated and start to wrinkle.
If you suspect that your fishbone cactus might be underwatered, remove it from its pot and note the consistency of the potting mix around the plant’s roots. If the soil is very dry and falls apart easily, then your plant is underwatered.
Return it to its pot and give it a little water – around a quarter of the volume of the pot. Water your fishbone cactus once a day, every day, for a week, adding a quarter of the pot’s volume in water every time you water it. It is better to slowly hydrate the plant and the soil rather than immediately soaking all of the soil, because you do not want to overwhelm the plant’s already weakened roots.
After a week of gradually increasing the plant’s water intake, it should be showing noticeable signs of improvement. Then, refrain from watering it again until the top two inches of potting mix are dry to the touch. If the potting mix is still damp, wait a few more days before checking on the moisture level again.
The best way to prevent underwatering your fishbone cactus in the future is by developing good watering habits: learn to tell when the plant needs to be watered by feeling the moisture level in the soil.
Overwatering
Giving your fishbone cactus too much water and causing its soil to become waterlogged can also cause the plant to wrinkle.
Overwatering can stem from giving your plant too much water every time you water it, watering it more often than necessary, using poorly-draining potting mix and pots, or not adjusting your watering habits to changes in the weather, season or climate.
While an overwatered fishbone cactus does look shriveled and wrinkled, the main indicator when you are dealing with overwatering is that the plant’s stems will feel soft and mushy to the touch. This mushiness comes about because the roots are drowning and starting to rot due to prolonged exposure to soggy soil.
When the soil is waterlogged, the roots will continue to absorb water to the point that the cells in the plant’s tissues burst from fullness. Furthermore, the rot in the dead roots will eventually travel up into the plant’s stems. The excess water in the plant’s cells, as well as the rot reaching the stems, are the reasons that the stems become soft and mushy.
Eventually, the stems will wrinkle because the defective roots can no longer absorb the water and the nutrients required for the plant’s survival.
Often, a fishbone cactus with mushy stems is too far gone to salvage. This is why it is best to know the early signs of overwatering, so that you can increase your chances of being able to save your plant.
If you think your fishbone cactus is overwatered, transfer it to a sunnier spot with good airflow as soon as possible. The heat from the sun and the airflow will help to dry the soggy soil faster.
Refrain from watering the plant again until you are sure that all of the soil in the pot is dry.
If you suspect root rot, you will need to unpot the plant to inspect the roots. Gently shake or wash off as much soil as you can from the roots, taking care not to damage them, as they will be fragile in their compromised state.
Inspect all of the roots closely, looking for sections that have turned brown or black. These roots are rotten and will have to be removed. Do this using a sterile knife or scissors, until only healthy, white roots remain.
Place your fishbone cactus on a dry, flat surface and let the roots air-dry for a few hours.
Fill a new pot halfway with fresh, well-draining succulent mix, place the plant in the middle of the pot and cover all of the roots with more potting mix as needed.
Do not water your fishbone cactus immediately after repotting it; allow a week for its roots to recover from the trauma of being pruned and replanted.
The best way to prevent overwatering in the future is by always checking whether the top two inches of soil are dry to the touch before watering it.
Use a potting mix specially formulated for cacti or succulents, because regular potting soil is too dense and retains too much water to be good for your fishbone cactus.
The pot or container you use is also a major factor in keeping the soil safe from overwatering. Make sure that your pot has drainage holes at the bottom, so that any excess water can easily drain out.
Also be mindful of changes in the weather or the season, and adjust your watering habits accordingly.
Low temperatures
As we mentioned above, the fishbone cactus is a tropical succulent from Mexico. It likes to grow in warmer weather and may struggle to remain healthy in colder climates.
If your fishbone cactus is kept in a cold environment, its stems might become wrinkled and mushy.
Aside from any considerable drop in temperature, cold drafts can also have the same negative effect on your plant. And, if you mist its stems and then leave it exposed to cold drafts, the stems will be at risk of rotting due to fungal growth. If you do mist the plant, make sure that it gets lots of light so that the water droplets evaporate quickly from its foliage.
Keep the plant in a room where the temperature is between 60 and 75 degrees Fahrenheit at all times.
If your wrinkled fishbone cactus is positioned under an air conditioning vent or near a door or window where cracks can let in cold drafts, move it to a different spot where it will be protected from cold air. After a few days, it should show signs of improvement.
As long as you keep the temperature around the plant within its preferred range and away from cold air and drafts, you should not have to worry about it becoming wrinkled due to low temperatures.
Excessive sun exposure
If you leave your fishbone cactus under direct sunlight for several hours each day, it is possible that its stems will dry out and become wrinkled.
Again, this is a tropical succulent that prefers indirect light, just like it would get in its natural habitat. Its foliage is far too sensitive to tolerate the intense light and heat of full sunlight, which will scorch its stems.
If you think that too much sun exposure is causing the wrinkling on your fishbone cactus, you need to move it to a shadier spot immediately.
If you keep it outdoors, try placing it under the shade of a large tree. Indoors, place it next to a north- or east-facing window. These windows let in bright, gentle light in the morning, but are in the shade during the afternoon when the sunlight is at its most intense.
If the only windows in your home let in very harsh light, you can still place your plant near them, but first hang a sheer curtain over the window to help diffuse the light’s intensity.
Usually, if your fishbone cactus is scorched and sun damaged, you will find that the soil in its pot has also dried out from the heat. Check the moisture content in the soil by touching it and, if the top two inches are dry, water it as soon as possible.
You cannot reverse the sun damage on your plant’s stems; all you can do is wait for them to grow out while continuing to care for the plant as best you can so that its new stems will remain healthy and green.
Conclusion
The fishbone cactus is a tropical succulent with a unique zigzag pattern in the shape of its stems that resembles a fishbone. It originates from Mexico, where it grows on the trunks and branches of larger trees in the forest.
This plant likes humidity and needs to be watered more than the average desert cactus. And, while it is relatively low-maintenance, it does have its share of common problems, one of which is the wrinkling of its stems. The possible causes of such wrinkling are underwatering, overwatering, low temperatures, and excessive sun exposure.
Seeing your fishbone cactus wrinkled up and looking unhealthy can be very worrying, but as soon as you can figure out the cause of the issue, you can take action to resolve it and return your plant to full health.
Image: istockphoto.com / IKvyatkovskaya