When your Calathea has yellow leaves, it is the plant’s way to inform you that there is an issue that needs to be addressed ASAP.
In most cases, the discolored foliage is not something you should ignore, and could potentially be a symptom of a much larger and more serious issue.
Let’s take a look at why your Calathea has yellow leaves and what you can do to correct the problem.
Why are my Calathea’s leaves yellowing?
When your Calathea has yellow leaves, the most common culprit is overwatering, but that isn’t the only cause of the discoloration. In fact, there are several other issues that can cause the Calathea’s leaves to yellow.
Overwatering is usually the culprit when your Calathea has yellow leaves. When the roots are soggy, they cannot properly absorb nutrients, which results in the discolored foliage.
If the overwatering continues, the plant will develop root rot and eventually succumb to the disease.
2. Growing the Calathea in poor soil
Compact and poor soil is directly connected to overwatering since the soil won’t allow excess water to escape. This can also lead to the Calathea leaves turning yellow.
3. Temperatures that are too hot or too cold
Calatheas need warm temperatures year round and don’t do well when the temperatures drop below a certain degree.
If you allow the plant to live in an environment that is too cold or too hot, the plant will start to go into shock. This can cause the leaves to yellow and even fall off the plant.
4. Direct sunlight
Like most houseplants, Calatheas do not do well when placed in direct sunlight.
Not only is this light too harsh for the plant’s leaves, but it can cause its foliage to burn, scorch, and turn yellow.
5. Poor water quality
Calatheas are sensitive to water quality, and trying to hydrate this plant with tap water can cause its leaves to discolor.
This is because tap water is filled with minerals and additives that can damage and discolor Calathea leaves.
6. Soil is too dry
Just like overwatering the plant, not providing enough water could be the reason why your Calathea has yellow leaves.
When the soil is too dry, the leaves can yellow or brown, start to wilt, and even fall off the plant.
You may also be interested in: Calathea in LECA: Ensure Your Prayer Plant Thrives
7. A dry environment
Calatheas are tropical plants native to areas with humidity levels that are a bit higher than what you usually have in your home.
This lower humidity means a drier environment, which can result in yellowing leaves.
8. Stress from being in a new home
The acclimation process can put stress on any plant, including the Calathea, and can even cause its leaves to start to yellow.
Thankfully, this issue will typically correct itself over time. Just keep providing the Calathea with its optimal care requirements to keep it healthy and happy.
9. Poor or incorrect fertilization
Fertilization of calathea is an important part of gardening, but it can also cause problems if not used correctly.
Fertilizer that is old or of low quality, as well as adding the wrong type or too much can all cause the Calathea to have yellow leaves.
10. Pest infestations
Like most other houseplants, Calatheas are not immune to the occasional pest infestations.
These sap-sucking insects pierce the leaves and stems with their sharp mouthparts and suck the vital juices out of the plant.
Not only does this cause tiny discolored spots to form where they inserted their needle-like mouths, but it can also result in the leaves turning yellow.
11. Old and dying leaves
Another potential reason as to why your Calathea has yellow leaves is simply that the leaf is old and dying. This is a natural process that occurs in even the healthiest of plants.
There is nothing you can or should do to try to correct the issue because it isn’t a problem at all. It is the plant’s way to get rid of these old and dying leaves, making room for new, healthy leaves to emerge.
How do you fix yellow leaves on Calathea?
The best way to fix yellow leaves on Calathea is to ensure you are providing the plant with its ideal growing conditions. In particular, given that overwatering is the most common cause of this, make sure you are giving the Calathea only the water it needs.
1. Only water the Calathea when its soil is dry
Overwatering is the leading cause of yellowing leaves, as well as the common cause of root rot. It is also completely preventable.
Water the Calathea only when its soil starts to feel dry, and you will go a long way to preventing yellowing leaves.
2. Avoid underwatering the Calathea
On the flip side of the coin, however, underwatering the Calathea can also cause yellowing leaves. While you shouldn’t overwater the plant, you should also avoid underwatering it as well.
The best way to ensure you give the Calathea the correct amount of water is to test the soil dryness level and only water when it begins to feel dry.
3. Plant the Calathea in soil that drains well
Soils and growing medium that doesn’t drain well will not only cause the Calathea leaves to turn yellow, but it also increases the chance of root rot.
To help prevent this from occurring, grow the Calathea in soil that isn’t compact and allows for good drainage.
You may also be interested in: Best Calathea Soil: Tips to Pick the Right Potting Mix
4. Maintain Calathea’s optimal temperature range
Calathea plants grow best in temperatures from 65 to 85 degrees. To help prevent new leaves from yellowing, make sure the room the plant is growing in stays within this temperature range.
Furthermore, keep the Calathea away from any areas in your room where there are extreme temperature fluctuations.
Areas like underneath or near a heating and cooling vent or next to a drafty door can all cause the Calathea to go into shock, which can cause yellowing leaves.
5. Keep the Calathea out of direct sunlight
Calatheas thrive when they have at least 8 hours of indirect sunlight. Select a sunny window indoors where the light shining through is filtered, such as through a sheer curtain or blind, and then place the Calathea next to it.
This should provide the plant with the right sunlight to keep its leaves from turning yellow.
6. Water the Calathea with distilled water
Tap water is filled with chlorine, minerals, and other activities that can leave the Calathea with discolored foliage.
Avoiding tap water and using distilled water is the way to go when it comes to watering this plant. You can also use filtered water or rainwater as well.
If you have nothing but tap water, however, you can still hydrate the Calathea. Just allow the water to sit on your counter for 12 to 24 hours before using it to water the Calathea. This will allow the chlorine that is typically added to tap water to dissipate.
7. Increase the humidity level in the room
A dry environment will quickly cause the Calathea leaves to yellow and wilt. Increasing the humidity level in the room to at least 50 percent will keep the leaves looking their best.
A quick way to increase the humidity level is to sit the Calathea on top of a drip tray, use a humidifier to put moisture into the air, or mist the Calathea’s leaves.
All of these methods will help to prevent the plant from drying out.
8. Be mindful of what type and how much fertilizer you give the Calathea
Calatheas are not heavy feeders, but that doesn’t mean you shouldn’t fertilize them every so often.
When you do feed them, use a balanced liquid fertilizer and dilute it by 1/2 its strength. Give it to the plant no more than once a month during its active growing season.
9. Watch for pest infestations
Even though pests are usually not a serious problem, they can cause the Calathea leaves to yellow. Additionally, pest infestations make plants more susceptible to diseases.
Regular examination of the plant will help you quickly spot pests before their numbers become too large.
If you do find pests, treat the Calathea with insecticidal soap. This safer pesticide is sprayed liberally onto the plant and will coat and suffocate the insects. It is safe to use indoors and won’t harm people or pets.
Should I cut yellow leaves off Calathea?
Yes, removing yellow leaves from a Calathea can help improve the overall appearance of the Calathea plant, while also making room for new growth. In addition, it ensures the plant’s energy is only used on healthy foliage, improving the Calathea’s overall health.
However, keep in mind that removing yellow leaves can cause the Calathea to look less full. Additionally, removing an abundance of leaves can even be detrimental to the plant’s health if you don’t leave it enough foliage.
If you do decide to prune off the leaves, do not remove more than ¼ of the Calathea’s leaves and only use a pair of clean and sanitized pruning shears.
Can yellow Calathea leaves turn green again?
Unfortunately, once the Calathea leaves turn yellow they won’t revert to their original green color. The good news, however, is that once you fix the issue causing the yellowing leaves, any new leaves that emerge will keep their stunning green hue.
If you allow issues to continue to pop up, however, any new leaves or green leaves that didn’t initially turn yellow will discolor.
Why does my Calathea have yellow leaves with brown edges?
When your Calathea has yellow leaves that are brown on the edges, the issue is usually with the water quality. Tap water is filled with chlorine, salts, fluoride, and minerals. These items can take their toll on your plant and even build up in Calathea’s soil.
The best way to prevent this from occurring is to stop using tap water and only water the Calathea with distilled water. If you have been watering the Calathea with tap water, you will need to flush the soil to remove any buildup of additives.
To flush the Calathea, simply hold the plant under running water. Try to keep the water from splashing directly on the Calathea leaves and instead position the plant so that the water runs directly into the soil.
Why are my Calathea’s new leaves yellow?
When your Calathea’s new leaves are yellow, the issue is typically caused by inconsistent watering. This can be either overwatering, underwatering, or a combination of the two. To correct the problem, simply maintain a proper water schedule, making sure to water only when the soil starts to feel dry.
You’ll quickly start to notice new growth coming in that’s the normal color.
Why does my Calathea have yellow leaves that are curling?
When the Calathea has yellow leaves that are curling, it is most often caused by underwatering. Underwatering can quickly cause the leaves to yellow, curl, and feel dry and brittle. If you continue to neglect the plant, the leaves will wilt, die, and fall off the Calathea.
Thankfully, this is one of the easier problems to fix, since you just need to water the plant. If the plant is severely underwatered, you won’t be able to water it using conventional methods, since the water will just roll right off the dry soil.
Instead, fill a container that is large enough to hold the Calathea pot with water. Set the Calathea in the water, making sure the top of the pot is fully submerged, and then let the plant soak for 20 to 30 minutes.
After the allotted time, remove the pot from the water and let all the excess water drain out of the Calathea’s container before placing the plant back in its desired location.
Why does my Calathea have yellow leaves after repotting?
Repotting a Calathea is sometimes a necessary task if the plant has outgrown its current container or if an issue, such as disease, arises. Repotting is also a traumatic experience for any plant, and can cause it to go into shock. When a plant is in shock or stressed, its leaves can be yellow.
While this isn’t a good thing, there isn’t much you can do about it. Simply continue caring for the Calathea and new leaves should emerge green and not yellow.