Why Has My Cactus Turned Purple?

A cactus that is purple can be caused by a variety of factors. Certain cactus will naturally turn purple, however it could be an indication that there is something wrong. Find the reason your cactus is changing color so that you can aid it in its growth.

Most often the cactus turns purple is a sign of environmental stress. Insufficient sunshine, temperatures issues and root rot, nutritional deficiencies, overcrowded roots and cactus cysts are the most likely reasons. In addition, your plant could be healthy and just adjusting to the new environment.

Is A Purple Cactus A Cause for Concern?

If your cactus’s color is changing purple, it’s not always an indication of a serious issue. For certain types of cactus, it’s common to see a little bit of purple.

It is a normal aspect of their lives when they encounter dry, cold conditions.

Could It Be Fruit?

If you own an Prickly Pear Cactus, you might be lucky. There’s a good chance that the spot of purple on your cactus actually an actual fruit!

Prickly Pears are sweet fruit which are utilized in many Mexican dishes. They vary in hues ranging from green to reddish-purple, and may appear like a discolored spot on the Cactus.

Purple Cactus

Causes of Cactus Turning Purple

Changes in color can be an issue If a large portion of your cactus’s leaves appear to be a shade darker.

Other indicators of a problem are wilting, stunted growth or soggy leaves. It is important to identify the reason for the change in color to determine if the plant is in danger.

Cacti alter color when they are under stress. Cacti have a purple pigment known as betalain. They produce more often as an expression of stress.

Let’s look at the possible causes and determine how to address them.

How to Treat Sun Scorched Cactus

Fortunately, the solution to sunburn is fairly simple. Transfer your cactus to an area that receives the least amount of direct sun.

Do not move it into your basement now, Cacti require a lots of sunshine!

Direct sunlight that hits directly on the plant, such as through a south-facing window can be considered direct sun.

The other windows in your home can provide indirect sunlight which can be distributed more evenly and less demanding on plants.

Transferring your plant to an area that faces the opposite direction could aid in reducing the sun’s scorching.

If you have only windows facing south, you can make an easy sun filter. Just prop a towel on top of your cactus plant to provide it with much-needed shade.

Too Much Sunlight

Although cacti evolved to thrive in bright light however, the one you have in your home may be struggling adapting.

Cacti that are sold in stores have typically been planted in shade in the greenhouse. This means they’re not exposed to a lot of direct sunlight.

Cacti require bright light however, it is best to have the light diffuse and indirect. When exposed to a cactus in a sudden manner, intense light could cause scorching to the skin of the cactus, causing it to change to a red-purplish hue.

If your cactus is brand new or you’ve recently relocated it to a more sunny location, there’s a high possibility that it’s sunburned.

Temperature Issues

The color of the leaves could be an indication of stress caused by temperature. Cacti often turn reddish-purple when their roots get too hot.

Cacti also change color when they are too cold. When the plants suffers from freeze injury, the cells explode and the plant is no longer capable of holding liquid.

How to Fix Temperature Stress

The ideal temperature lies between the two, which is why it is important not to place your plant in extreme temperatures.

To keep your cactus from becoming too cold, keep it from cold and drafty areas like doorways and glass. Avoid areas that are too dry and hot such as fireplaces and heating vents.

The plant’s roots are the ones most likely to get hot, make sure you place your cactus in a container that is cool. Avoid plastic planters that are black and opt for clay or other materials.

Root Rot

The purple leaves can also be an indication of root rot that is caused by overwatering as well as poor drainage.

If the soil remains wet for too long the roots of your plant will die and not be able to absorb the nutrients and water such as magnesium. In the end, your cactus could change color to violet.

How to Fix Root Rot

Start by cutting off the damaged leaves and roots with sterilized scissors. Then, you can remove as much of the sloppy dirt as possible.

Place the plant in an unclean pot filled with fresh pots and soil. Do not water the cactus for several days after the move, and let the soil’s top inch dry out between irrigations.

The majority of the time, root rot is a result of excessive watering. I’ve written an article about how to help your cactus that has been overwatered. Also, you will be taught how to properly water them.

Nutritional Issues

One reason your cactus’s color is changing is that it lacks the right nutrients it requires to thrive. When your plants are dying and is turning purple, it could be an indication of a magnesium deficiency.

Cacti that are decorated for Christmas are more susceptible to developing magnesium deficiency. However, all kinds of cacti can be affected.

How to Treat Nutritional Issues

If your cactus has an absence of magnesium fertilizer is the answer. It is possible to purchase fertilizers that are magnesium-enriched, but you could also take the DIY option by using the Epsom salt application.

To create a magnesium treatment make the following mixtures in a spray bottle:

  • 8 tablespoons Epsom salts
  • 2 and 1/2 gallons water
  • Two drop of detergent for dish washing

Make use of a spray bottle to spray the leaves of the Cactus, but make sure to also spray the undersides of the leaves. Continue to spray the mixture for two weeks, until the cactus returns to its usual shade.

Crowded Roots

Roots that are crowded could be another cause for the cactus’s color changing. If the plant is placed in a pot that is too small, the roots may become too crowded and, in turn “rootbound”.

Rootbound plants aren’t able to effectively absorb nutrients and water out of the soil. A deficiency in nutrients could cause plants’ leaves to change color due to an expression of stress.

How to Fix Overcrowded Roots

As time passes, your cactus root system will get larger and may not be able to fit in the pot that it was once be.

If you observe that certain areas of the root are trying make it out of the drainage hole, then it’s time to move your cacti in a larger container. It is recommended to repot your Cactus every 3 to 4 years.

If the roots of your cactus are getting too crowded it is time to relocate it to an area that is larger. In general it is recommended to repot the cacti once you are able to observe their roots through the drainage holes in on the sides of your pot.

For cactus species that grow faster typically, this takes between about two up to 3 years. Cacti that are slower growing are best repotted every three or four years.

Different species of cactus require the same conditions It’s crucial to determine the best conditions for your Cactus.

For instance, certain kinds of cactus, such as Christmas cacti can thrive with roots that are crowded.

This is why a Christmas cactus shouldn’t be relocated unless it’s had the pot in place for at least several years.

These are steps you can follow to repot your cactus:

  1. Before you plant your cactus again, first make sure you’re wearing gloves that are thick to shield your skin from the plant’s sharp spines.
  2. Examine the soil and plant for signs of pests or indications of disease
  3. Choose a container that is that is bigger than the one you had previously.
  4. Put gravel in the base of your pot to assist in drainage. Then, sprinkle a thin layer of gravel over the top of the soil
  5. Let the soil drain before you resuming your normal watering schedule

Source: Cactus & Succulent Society of San Jose

Cactus Cyst

A cactus that is purple could be an indication that you have an illness. It is possible that your plant has been infected by a pathogen known as Cactodera cacti, also called Cactus cyst.

Cactus cyst develops when a cactus plant is placed in soil that is infected. The reddish-purple color of the leaves and wilting, along with slow growth and wilting are all possible symptoms of the infection.

The most noticeable indication of a cactus cyst however, are tiny white spheres appearing on the roots of the plant. (Source: Plantwise Knowledge Bank)

How to Treat Cactus Cyst

It’s very difficult to deal with the cactus cyst after it’s infected with and spreads to other plants, so concentrate on prevention rather than. To stop your cactus from becoming sick put it in well-sanitized, clean soil in a fresh pot.

If your cactus is infected, the best option is to throw it away. Although it may be difficult to dispose of your beloved cactus, it’s vital to stop the infection from spreading to your other plants.

Have you ever had to deal with an cactus that has turned purple? What was the cause and what did you do to bring back the plant?



Went from a bad gardener to a half-decent one over 10+ years. Super happy to share my tips and tricks with you :)