Why Is My Cactus Turning White?

If you’ve noticed your beloved cactus turning white, it can be quite alarming. Cacti are known for their vibrant green color, so when they start to fade and appear white, it’s natural to wonder what might be causing this change. Several factors can contribute to a cactus turning white, ranging from natural processes to underlying issues that require attention. Understanding these reasons can help you identify the problem and take appropriate measures to restore your cactus’s health.

Lack of Sunlight

One possible reason for your cactus turning white is a lack of sunlight. Cacti thrive in bright, direct sunlight, and when they don’t receive enough light, they may develop a pale and discolored appearance. If your cactus is growing in a shaded area or is placed indoors away from windows, it is not getting the sunlight it needs. Consider moving your cactus to a sunnier spot or supplementing natural light with artificial grow lights.


Believe it or not, just like humans, cacti can also experience sunburn. When exposed to intense sunlight for prolonged periods, cactus tissue can become damaged and turn white. This is especially common in cacti that are suddenly exposed to very strong sunlight after being kept in shade for a long time. To prevent sunburn, gradually introduce your cactus to more sunlight, starting with short periods and gradually increasing the duration.

Powdery Mildew

Powdery mildew is a fungal disease that can affect cacti and cause their surface to turn white. This fungus thrives in warm and humid environments, so if your cactus is kept in an area with poor air circulation or excessive moisture, it may be susceptible to powdery mildew. To treat this problem, carefully wipe the affected areas with a cloth dampened in a solution of water and mild soap. Make sure to keep your cactus in a well-ventilated location to prevent further fungal growth.

Mealybugs Infestation

Mealybugs are small insects that can infest cacti and cause them to turn white. These pests typically appear as cotton-like masses on the surface of the cactus and feed on its sap, weakening the plant and affecting its color. To eliminate mealybugs, you can use a cotton swab dipped in rubbing alcohol to gently remove them from the affected areas. If the infestation is severe, you may need to consider using horticultural oils or insecticidal soaps specifically designed for controlling mealybugs.


If you’ve been neglecting to water your cactus, it may begin to show signs of distress, including a whitening of its surface. Underwatering can lead to dehydration and cause your cactus to lose its vibrant green color. To remedy this issue, thoroughly water your cactus and ensure that it is receiving adequate moisture. However, it’s important to strike a balance, as overwatering can also harm your cactus.

Table: Quick Tips to Prevent Cactus from Turning White

Provide ample sunlightCacti need at least 6 hours of direct sunlight daily to stay healthy and maintain their vibrant color.
Avoid sudden sun exposureGradually introduce your cactus to increasing amounts of sunlight to prevent sunburn.
Ensure proper air circulationKeep your cactus in a well-ventilated area to prevent the onset of powdery mildew.
Inspect for mealybugsRegularly check your cactus for signs of mealybug infestation and promptly address the issue.
Water appropriatelyFind the right balance between providing enough water to prevent dehydration and avoiding overwatering.

In conclusion, if you notice your cactus turning white, it’s essential to investigate the underlying cause and take appropriate action. It could be due to a lack of sunlight, sunburn, powdery mildew, mealybugs infestation, or underwatering. By understanding these factors and following the mentioned preventive measures, you can help ensure that your cactus maintains its vibrant green color and remains healthy and happy for years to come.