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Why Is My Cactus Turning White? Reasons and 4 Easy Solutions

Cactus is an enigmatically tough plant when it comes to lighting. Native to the harsh desert environment of North and South America, these prickly pear cacti are not afraid of the sun.

Cacti — being very resilient plants, usually cause people to entirely neglect to care for them. This mistake leads to quite a few problems. One of the most common ones is your cactus turning white.

When I think, “Why Is My Cactus Turning White?” There are a couple of caring domains that hop into my brain. I wonder if I’m being a little offhand in any of them. And after diagnosing the problem, I can easily save my gorgeous green buddies from going extinct.

Cactus plant turning white from bottom fading towards the top.
“My cactus is turning white; what can I do?” via Reddit.

So, what are those caring domains that you might be neglecting?

There are 4 most potential reasons for a beautiful green cactus to turn white.

Let’s dive into the article, and explore the most common mistakes people usually make while working with cactus plants.

Why Is My Cactus Turning White? – Potential Reasons

The leading cause of a fading cactus plant is sunburn.

Cause #1: Sunburn

It might come to your surprise, and you might be thinking, What?… Sunburn? But let me tell you something.

I know that cacti are desert plants, and they thrive in the bright sunlight of their natural habitat. But there are certain aspects of these habitats that you don’t know.

First of all, most cactus species naturally grow on the slopes of the rocks, where they get shade from the burning rays of the midday sun. Also, most land cacti grow among other higher plants like thorns that can scatter direct sunlight.

Therefore, placing it in direct and harsh sun rays, mostly during summers, can cause your cactus to turn white.

Why is my cactus turning white? It isn’t soft and is still green at the bottom.
“Why is my cactus turning white? It isn’t soft and is still green at the bottom.” via Reddit.

Solution

Cactus plants love direct sunlight because they are succulent plants. But it is essential to be careful about the time of the day in which you provide your plant with the light.

As the midday and afternoon sun is coarse and hot, you should restrain placing your cactus under the direct rays during this time. You can use shade cloths or cardboard to cover your plant from burning rays if you can’t relocate it.

But if you can relocate your cactus, you must be careful about the orientation in which you place it.

While sitting outdoors, your cactus plant develops sun tolerance on the south-facing side. And when most people transfer their cacti indoors, they place them in front of a south-facing window so that they get sufficient lights.

But, if you place the intolerant side in front of the south sun, your cactus can turn white due to sunburn. So, make sure you keep the same orientation by facing the tolerant side towards the sun.

Cause #2: Overwatering

Overwatering is the last thing you need while caring for a cactus plant.

As you know, these remarkably hardy plants can tolerate bone dry conditions for a very long time. Cacti are succulent plants that store water in their stems in the form of sap. That’s why they can live up to a month without watering.

Overwatering your cactus combined with a poor potting mix (not well-draining) leads to ROOT ROT.

A cactus with root rot turns soft and mushy, leaves and stems show yellow (sometimes white) discoloration, and the plant turns brown.

Solution

If you diagnosed the root rot early on and healthy roots are still present, you must re-pot your cactus into a new, fresh, and well-draining potting mix.

Make sure to use a pot with lots of drainage holes at the bottom. Your potting mix should also be breathy and well-draining to prevent further root rot problems.

Regarding watering your cactus, mostly cactus plants need watering once a month.

Before giving your plant another shot of hydration, use a moisture meter or a probe to check if the soil is entirely dry or not. If it is dry, then you can water your plant again.

Cause #3: Pest and Fungus Infestation

Your cactus can turn white due to a pest infestation or a fungal infection.

Mealybugs are the most common sap-sucking pests that feed on cactus plants. They leave behind white residue on the leaves of most plants. As cacti do not have leaves, the white residual spots usually spread on the whole plant giving it a white look.

Also, many spores in the air can cause fungal infections in your cactus in higher humidity or high moisture levels. This usually happens when you frequently water your plant.

High moisture level attracts sap-sucking pests. It is a contributive factor in pest infestation.

Solution

Both of these problems are swiftly treated using homemade insecticides and neem oil.

You can use suitable gardening tools to brush off the bugs from your cactus. Then simply apply some rubbing alcohol to save it from further infestations.

Use neem oil spray to get rid of any fungal infections, and be sure to make a proper watering schedule for your cactus, as explained above.

4. Inadequate Light

Inadequate light is another major problem that causes the cactus to turn white. Most succulent plants, including cacti, stretch out due to insufficient light intensity. This process is also called succulent etiolation.

Why your thin cactus is not growing healthy?
“Why your thin cactus is not growing healthy?” via Reddit.

In this case, the plant does not produce enough chlorophyll — the pigment responsible for the green color in plants. And the plant gets elongated towards the light source in search of more light.

Solution

If you’ve been placing your plant in a spot without enough light, try moving it to a brighter spot, and see if it aids or not.

But if you already have your plant outdoors or in front of a south-facing window, where it gets adequate light, then maybe your cactus turned white due to sunburn or some other reason.

Observe the conditions you are providing to your plants, and you will be able to fix them effortlessly.


Conclusion

With all that said, I hope that today’s article helped you with your white cactus. Now you know why your cactus is turning white.

I would like to highlight that if your cactus is sunburned or corked (natural changing of color: usually fading of green color as the plant matures or gets old), the change is permanent and can’t be recovered.

If you enjoyed today’s talk, make sure to share it with your friends and family. On that note, stay safe and keep your green buddies safe too.

Regards, Mahad H.