Why is My Cactus Shrinking? 4 Reasons Why & How To Save It

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If you’ve been keeping a cactus as a houseplant, and have noticed that it’s been gradually shrinking, you may be wondering “why is my cactus shrinking?”. In this post, we will explore four possible reasons why your cactus is shrinking, and provide tips on how to save it!

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Why Did My Cactus Shrink?

The 4 main reasons your cactus may be shrinking include: not getting enough water, not getting enough sunlight, overwatering, and rotting.

Cactus Shrinking From Underwatering

The first reason why your cactus may be shrinking is that it’s not getting enough water. While cacti are known for being drought-resistant, they still need a good watering every once in a while to stay healthy. If you notice that your cactus is starting to wrinkle or shrivel and you haven’t watered it in a while, this is a sign that it’s not getting enough water.

To save your cactus from underwatering, be sure to give it a good soaking once every week or two (but less during winter). If possible, try to use filtered or distilled water so that your cactus doesn’t get too much mineral build-up. Allow the soil to dry out completely before watering again.

(Read how often should I water my cactus!)

Just be sure to check the soil before watering it to make sure you don’t overcorrect and overwater your cactus!

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Cactus Shrinking From Not Enough Sunlight

Another possible reason why your cactus is shrinking is that it’s not getting enough sunlight. Cacti need a good amount of bright, direct light to stay healthy, and if they don’t get enough, they will start to stretch out and become leggy in an attempt to reach the light. If you notice your cactus stretching and falling over, or becoming etiolated (plant looking white), this is a sign that it needs more light.

To save your cactus from not enough sunlight, simply move it to a brighter spot in your home or office. Be sure to give it a few hours of direct sunlight every day, or in a spot where it gets full sunlight every day. You may also want to consider investing in grow lights if you don’t have a lot of natural light, especially in winter.

Read for how to encourage your cactus to grow faster

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Cactus Shrinking From Overwatering

The third reason why your cactus may be shrinking is that you’re overwatering it. While cacti need to be watered every once in a while, too much water can actually do more harm than good. If your cactus is sitting in water or the soil is constantly soggy, this can lead to root rot, which will kill your cactus.

To save your cactus from overwatering, be sure to only water it when the soil is dry to the touch. Allow the water to drain completely and don’t let your cactus sit in water. If you think your cactus has root rot, you can try repotting it in fresh, dry soil.

You can easily check if this is the case of why your cactus is shrinking by just feeling how wet the soil is. And keep in mind, the less sunlight your cactus is getting, the less water it will need.

Cactus Shrinking Because It’s Rotting

The fourth and final reason why your cactus may be shrinking is that it’s rotting. If your cactus is getting too much water or not enough light (or both), this can lead to the plant rotting from the inside out. This is usually signaled by brown or black spots on the plant, as well as a general mushiness.

Another reason your cactus may be shrinking from rot is if, when you water it, water gets on the cactus itself, rather than just the soil. Cacti do no not like water on themselves.

If you think your cactus is rotting, the best thing you can do is try to save it by repotting it in fresh, dry soil. If the rot has spread too far, however, you may need to start over with a new plant.

Or if the rot is mostly at the bottom of the plant, cut across the plant, removing the rotten part. Then, allow the bottom of the newly cut piece for a few days, and then put it on top of some soil.

Final Thoughts For Why Is My Cactus Shrinking?

There you have it! Those are the four main reasons for “why is my cactus shrinking”, as well as how to save it. Be sure to check the soil moisture and sunlight amounts it’s getting to figure out why your cactus shrunk. If all else fails, you can always try repotting it in fresh, dry soil.

We hope this article helped you figure out why your cactus is shrinking and how to save it.

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Looking for information specific to Colorado? Check out Naturalist Perspective!

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