• Home
  • About
  • Contact
GlowGreenery
  • Plant Care
    • Pest Control
    • Plant Nutrition
    • Watering
    • Lighting
    • Propagation
  • Soil Selection
  • Plant Insights
  • Grow your Own
No Result
View All Result
  • Plant Care
    • Pest Control
    • Plant Nutrition
    • Watering
    • Lighting
    • Propagation
  • Soil Selection
  • Plant Insights
  • Grow your Own
No Result
View All Result
GlowGreenery
No Result
View All Result
Home Plant Care

Cactus Turning White: The Most Common Causes and Solutions

Caitlyn Palmer by Caitlyn Palmer
December 20, 2023
in Pest Control, Plant Care
Reading Time: 6 mins read
Cactus Turning White
Share on FacebookShare on Twitter

Table of Contents

Toggle
  • Overwatering as the Culprit
  • The Cactus is not Getting Enough Sunlight
  • Cactus Turning White From Overfertilization or a Lack of Nutrients
  • Cactus Turned White Because of Frostburn
  • Pest Infestation as the Cause for Cacti Turning White
  • Before you go…

Healthy cacti are usually vibrant green in color, and sometimes, you can meet a grafted cactus that is tinted orange. But white? That’s not the natural color!

If you see your cactus slowly turning white, don’t panic. There are many possible reasons why this may be happening and if you spotted it early on, it is very easy to fix too!

In this article, I will walk you through a few of the most common reasons why your cactus is turning white. Each issue manifests in a slightly different way, and I will describe it as best as I can so you easily uncover the real culprit.

Key Takeaways
White cacti coloration is commonly caused by the lack of sunlight, watering issues, or overfertilization
Overwatering can be observed as white, mushy spots on the plant
If the lack of sunlight is the culprit, you can notice your cactus stretching or leaning toward the nearest light source and the vibrant green slowly fading away
If the watering has its origin in nutrient deficiencies or overfertilization, you will often notice different coloration across the cacti depending on the nutrient lacking or abundant

Overwatering as the Culprit

If you've been a bit too generous with the watering can, your cacti might reveal its distress through white, mushy spots on the plant stem. These patches signal root rot, where excess moisture creates a breeding ground for harmful fungi. These spots can slowly turn brown as the plant tissue dies away. 

Cacti are succulent plants that are accustomed to infrequent but heavy watering. Allow the soil to dry completely out between watering to give the cactus roots a chance to recover.

Many gardeners, including myself, prefer the watering method of water bath. Using this method, you completely submerge the whole pot in the water, making sure all of the soil is under water. As the soil soaks all that liquid, it will bubble. Once the bubbling stops, lift the pot and let the excess drain off. Repeat as needed; I do this only once a month. This ensures your cactus gets enough water while leaving enough room to dry out.

Related articles

Heavy Rain After Planting Garden: Here’s How to Protect It

How to Grow Kaffir Lime Tree from Cuttings

If overwatering was on the regular schedule, it may be a good idea to repot the cactus and start again. Choose a well-draining soil and a bot with drainage holes at the bottom.

The Cactus is not Getting Enough Sunlight

Let sun do its work
If you notice the color slowly fading away and a stretched-out appearance, the likely culprit is insufficient sunlight. The discoloration or white appearance usually start to appear from the bottom of the stem slowly continuing upwards. 

This can be an issue especially during early fall, when it’s consistently cloudy but it’s not late or cold enough for the plant to go dormant. As a result, your cacti still work to the fullest, requiring a lot of sunlight that it doesn’t get.

To photosynthesize effectively, cacti need at least six hours of indirect sunlight each day. Relocate the pot to a spot where it can bask in the sun. South or west-facing windows are ideal, but if natural light is limited, consider supplementing with a grow light. Also, don’t forget to rotate the plant here and there to ensure all sides receive equal sun exposure and encourage balanced growth.

On the other hand, too much sun exposure is also an issue, but will rarely manifest as white or pale spots. If a cactus is under direct sunlight all day, you will rather notice brown, burned spots. These spots are caused by the UV rays, which destroy the living cells. However, the solution is the same—relocate the pot to a more suitable location.

Cactus Turning White From Overfertilization or a Lack of Nutrients

Nutrient Imbalance is one of the causes that can manifest in a many different ways. If the cactus gets more of a nutrient that it can absorb, it can build up on the surface of the plant and the soil as white, crusty deposits. This applies to minerals present in the water as well. On the flip side, a lack of nutrients or some nutrients in an excess amounts can make your cactus fade aways or make patches varying in color.

White patches on cacti due to overfertilization or the lack of nutrients are the hardest to reliably detect, at least without various test kits, which can get quite expensive.

If you think white spots on your cactus can be caused by overfertilization, cut back on fertilizing. Cacti should be fertilized only every 8 to 10 weeks during the growth season.

Mineral deposits can also be caused if you water with tap water, especially if your location has hard water. This will usually manifest as a thin layer of white dust on the surface of the plant, where the water evaporates.

Cactus Turned White Because of Frostburn

low temperature
Frostburn occurs when cacti, typically adapted to warm and arid climates, are exposed to a bigger temperature jump. The telltale signs are white or discolored patches on the surface of the cactus, often accompanied by a soft, mushy texture.

The damage caused by frostburn disrupts the plant’s cells, leading to a loss of pigmentation and structural integrity.

To remedy frostburn, first, assess the extent of the damage. Trim away any visibly affected areas with clean, sharp tools, leaving behind healthy tissue—my guide on How to Trim a Cactus to do it the right way can help you with that.

If the frostburn is extensive, consider moving the cactus to a warmer location or providing temporary protection during cold spells.

Pest Infestation as the Cause for Cacti Turning White

There are many insects and bugs that give away their presence by leaving a white, waxy residue on the cactus surface. Some tiny invaders can also lay tiny eggs closely together making a white patches on the cacti surface.

A white appearance on a cactus is often the result of bugs such as spider mites, aphids, and mealybugs. You might notice a white waxy residue on the plant surface called honeydew or cottony masses and small- shell-like protrusions on the cactus.

Left unchecked, a pest infestation can compromise the overall health of your cactus and contribute to overall dieback.

A minor pest infestation can be solved by simply wiping away the pests using a cotton swab dipped in rubbing alcohol. For a more extensive infestation, opt for an insecticide and quarantine the infected cactus to prevent the pests from spreading to other plants.

Before you go…

Dealing with ill plants, such as cacti with white spots, can be a bummer. Once your cactus is healthy again, you want to make sure it stays like that for a long time. And I have something to make sure your cactus looks the best it can because your cactus deserves to shine! Make sure to check out my guide on cleaning succulent leaves with a simple recipe for homemade leaf shine…

Source: Featured image by Katja Schultz
ShareTweetPin1
Caitlyn Palmer

Caitlyn Palmer

Meet Caitlyn, the founder, and author - a passionate gardener and plant lover with a degree in horticulture who turned her struggles with starting a business into creating GlowGreenery, a place where she shares her knowledge and love for indoor gardening with the world. Learn More about Caitlyn.

Related Posts

Heavy Rain After Planting Garden

Heavy Rain After Planting Garden: Here’s How to Protect It

December 27, 2023

Depending on the country, heavy rains can be more or less frequent, which can easily destroy our garden plants. But is it a cause of concern...

How to Grow Kaffir Lime Tree from Cuttings

How to Grow Kaffir Lime Tree from Cuttings

December 15, 2023

During times of flu and other infections, a lot of us reach for the lemons and other citruses. The Kaffir lime tree is especially valued in...

Brown Crust on Monstera Stem

Brown Crust on Monstera Stem? Here’s How to Fix It

October 2, 2023

You are caring for your Monstera as well as you can. But then something happens that you have never seen before: a brown crust forms on...

Small White Eggs in Soil

What are Small White Eggs in Soil and How to Deal with Them

October 2, 2023

Small white eggs can be found in many different places. But soil or composts are the usual target of the insect laying these eggs. However, don't...

How to Make Hoya Climb

This is Why your Hoya Need a Trellis: How to Make Hoya Climb

October 1, 2023

Hoyas, commonly known as Wax plants, are day by day more popular. I've got an email from many gardeners that they got Hoya because of my...

Next Post
Heavy Rain After Planting Garden

Heavy Rain After Planting Garden: Here's How to Protect It

Blue spider lily

Do Blue Spider Lily Exist? What is the Closest Flower to Them?

RECOMMENDED

Why are Mushrooms Growing in Monstera
Pest Control

Why are Mushrooms Growing in Monstera? What are Those?

April 10, 2023
How to Sterilize Soil
Soil Selection

How to Sterilize Soil: 6+ Techniques for a Pest-Free Garden

May 9, 2023
GlowGreenery logo+text

Let's create a beautiful garden together. We'll help make your plants glow with health and vitality!

© 2023 GlowGreenery. All Rights Reserved.

  • About
  • Contact
  • Privacy Policy
  • Terms of Use
  • Accessibility
No Result
View All Result
  • Home
  • Plant Care
    • Pest Control
    • Plant Nutrition
    • Watering
    • Lighting
    • Propagation
  • Soil Selection
  • Plant Insights
  • Grow your Own
  • Contact

© 2023 GlowGreenery. All Rights Reserved.