Why Is My Cactus Turning Yellow? (11 Reasons and Treatments)

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The cactus is one of the most popular plants in the world. They are unique and often beautifully colored, which makes them a favorite for many people.

However, despite their popularity, they can be somewhat difficult to care for.

It’s not uncommon for a cactus to turn yellow, mainly when it is being grown in an environment that is too dry or has the wrong lighting.

But why is my cactus turning yellow?

There can be many reasons why this happens, so it’s important to diagnose why before you treat it.

This blog post will go over why your cactus turns yellow and what you should do about it!

11 Reasons Why Your Cactus Is Turning Yellow

The most common reasons a cactus plant turns yellow are:

Overwatering

A cactus turning yellow is often the result of overwatering. Cacti need occasional watering but should be watered less than once a week in most cases.

If you overwater your plant, it will start to turn yellow (sometimes with some brown spots on its edges) and eventually die.

Make sure that there are no standing pools around the base of the plants or pots either, as this can also lead to over-watering problems like root rot or stem decay.

If you think that your cactus is turning yellow due to overwatering, try allowing the soil to dry out between waterings.

If this doesn’t solve the problem, make sure that there are no standing pools around its base and ensure it is getting enough sun and ventilation.

Not Enough Sun Exposure

One reason why your cactus may be turning yellow is that it needs more sun.

Cacti need a lot of light to grow and thrive, so if you’ve been keeping it in the dark for too long, its color will start changing as a result.

If the plant is outside, make sure that there are no obstacles blocking sunlight from reaching it.

In addition, check to see if any of your plants have been recently repotted and need more bright light before they begin sprouting new green growth.

The color of a succulent plant will also depend on its location in an interior setting because some types of artificial lighting can cause them to change its colors over time.

For an indoor cactus, make sure to place it where there’s plenty of natural light.

Too Much Sun Exposure

Cacti are desert plants, so they will need a lot of direct sun to grow.

However, if you plant your cactus in an area where it is exposed to intense sunlight, it can get fried and turn yellow.

It is common for a cactus to sunburn and turns yellow if the plant is left in a sunny spot for too long.

The best way to prevent this is by repositioning your plant so that it isn’t in direct sunlight all day.

You can also place your cactus plant in a spot with morning sun and afternoon shade or put up some type of screen to block the sun.

Yellowing can also happen if you move your cactus from a shady spot to a sunny area.

If the plant is not used to getting so much sun, it will be damaged by exposure and turn yellow.

But this won’t last forever! If you gradually expose your cactus to more sunlight over time, its natural defenses will increase too, which should prevent any further damage or yellow discoloration.

Not Enough Water During Hot Weather or Drought Conditions

A cactus will turn yellow when it does not receive enough water.

This can be caused by too much sun, drought conditions, or just leaving the plant in a pot for a few weeks without any watering at all.

To fix this problem, you’ll need to provide more frequent and thorough watering until the soil is moist again.

If there’s no rain or moisture in the air, misting may also help keep your plant from turning yellow.

If they live in a hot climate or drought conditions and your cactus has been yellow for several weeks, you may want to try the following:

First, check that it is not getting sunburn from being in a location that gets too much light.

If this is not why it’s turning yellow, then be sure to provide plenty of water and allow the soil to dry out completely before watering again.

You could also move your plant into an area with partial shade or near an open window where there might be some humidity in the air.

Poor Soil With Low Nutrient Content

If you’re growing your cactus plant in a pot with poor soil and low nutrient content, it will turn yellow.

Cacti need high-quality porous soil that is dense enough to hold water but not so heavy as to make the plant top-heavy or prone to falling over when watered.

Potting soil mixes specifically made for cacti (succulent/cactus soil) are usually highly recommended because they contain additional nutrients like iron and calcium, essential for healthy growth.

Temperature Change

Temperature changes are one of the most common causes of why a cactus turns yellow.

They can be caused by moving it from one location to another or placing it near something that causes significant heat, like an oven vent or heater.

If you have not moved your plant recently and the temperature has changed significantly in its current location, then this may be why your plant is turning yellow.

To prevent a cactus from turning yellow due to temperature change, move your plant to its new location over the course of several days.

By gradually moving it, you will prevent a cactus from turning yellow because of sudden temperature changes.

If you have not moved your plant recently and the temperature has changed significantly in its current location, then this may be why your plant is turning yellow.

When a cactus turns yellow due to sudden changes in the surrounding environment, it can take some time to recover from that change.

In this case, you should wait until the color returns before watering or fertilizing again. Otherwise, if water was applied too soon after the temperature change while staying at high temperatures, root rot could occur.

To help prevent cactus root rot, keep the soil moist but never wet when slowly transitioning plants between environments with significant temperature differences.

Too Much or Not Enough Fertilizer

Other reasons why a cactus may turn yellow are over-or under fertilization. When the plant doesn’t get enough water, it will start to show signs of stress and eventually turn yellow from lack of nutrients.

If too much fertilizer was applied in one day, this could also cause the surface leaves to turn brown and peel off as they decompose.

Excess fertilizers contain salts that build upon the soil’s surface, blocking moisture from going into roots.

This is hard to do, but the best way to “fix” this problem is by watering the plant regularly without adding any fertilizer for at least two weeks.

After a while, you can add fertilizer again slowly until the plant’s leaves look better and have grown new leaves.

Pests

One of the most common reasons why a cactus turns yellow is because pests are attacking it.

Usually, these are bugs such as mealybugs or spider mites that have built up lots of populations on the plant and suck all the nutrients out from its yellow leaves.

To avoid this, check your plants often for any signs of pest infestation–a little bit can quickly become overwhelming amounts before you know it!

Most importantly, make sure to get rid of any dead matter around or near your plant, so they don’t use those materials as food sources. Dead organic material will only attract more pests.

If you do find an infestation, the best solution I’ve found is to use neem oil.

You just apply it as you would an insect repellent–by spraying it on the plant and rubbing it well so that there are no white traces left behind. It doesn’t smell good but has amazing results!

Diseases

A cactus turning yellow is a sign of various diseases.

One common fungal disease that can cause this symptom to occur is called Cephaleuros wilt, caused by the fungus Verticillium dahliae (Vd).

This infection causes water-conducting tissues in the plant to die and lose their ability to transport water throughout the rest of its body. Yellow may also be from other symptoms associated with other illnesses such as chlorosis.

Chlorosis or iron deficiency most commonly affects cacti and succulents because they absorb very little nutrients from their environment.

You may notice your plant turning an overall lighter green color with speckles of light browns when this happens.

Though it can happen at any time during a cactus life, it usually occurs when the plant gets too much water (meaning overwatering) or not enough water (underwatering).

If left untreated for long periods, diseased cacti will die off altogether.

The solution is to repot them into fresh soil to get new nutrients and a better drainage system. Then, make sure to cut off any dead roots with a pair of scissors and provide plenty of direct sunlight right away!

Frost Damage

If the cactus is turning yellow because of frost damage, it may not be able to recover.

Frost damage can cause irreparable harm to a plant’s cells and tissues, resulting in permanent scarring on the surface of the leaves.

This type of injury usually occurs when temperatures drop below freezing overnight or during periods when light freezes happen over several days.

In this case, you can try moving your cacti into an area with more sunlight or higher humidity conditions if possible.

If the cactus was harmed by frost, then you may be able to help it recover over time if it’s left in a place where temperatures are about 50 degrees Fahrenheit.

As this area warms up and new growth begins to appear, move your plant back into its normal environment until all signs of frost damage disappear.

Exposure to Chemicals

Some chemicals can cause cacti to turn yellow. These include chlorine, fluorine, and other substances that are found in water or fertilizers.

If your cactus is turning yellow, it may be because of a nearby chemical spill or the excess use of these products around your plants.

If you suspect this might be why, try moving them elsewhere away from any potential sources for contamination- such as sprinklers used on lawns near where they’re sitting on the ground.

Final Thoughts

The answer to the question, why is my cactus turning yellow? It can be due to many different reasons.

You need to evaluate the cactus and the conditions it is in to figure out why.

The main thing to keep in mind when it comes to why your cactus is turning yellow is that you are not providing your cactus with the correct care.

This is why the first thing to do when your cactus starts turning yellow would be to look at what you are doing wrong.