Yellowing leaves on a ZZ plant are a sign of stress. There are many reasons why you plant may be stressed and we will cover all of them today in this article. There is no reason for you to stress though because we will also look at what you can do to fix yellowing leaves, you’ll be surprised how simple it really is.
The most common reasons why ZZ plant leaves turn yellow are:
Is moisture stress turning your ZZ plant leaves yellow?
Our plants are very good at telling us when there is something wrong, their leaves turning yellow is just one of the many cues they give. If your ZZ plant’s leaves are turning yellow it can often mean that they’re under moisture stress from either underwatering or overwatering.
To tell if your ZZ plant is under watered or over watered is quite simple, firstly you’ll know how much you water the plant however if you’re still unsure then put your finger into the soil, if you get a few inches down and there is no moisture then the plant is most likely underwatered. If your the top soil is constantly damp then the plant is most likely overwatered. Underwatered plants are often accompanied by dry or cracking leaves that can also curl up while an overwatered plant may be accompanied by dark or blacked stems near the soil level.
What to do if your plant is underwatered?
Simple, water your plant. There are some extra measures you can take to ensure that your plant is able to absorb the water it needs. Dry soil will let water pass through it and not hold the moisture. It is best to take a dry plant and put it in a sink or bathtub and run it under the tap for 15-20 seconds. This will ensure that the plant gets enough water to establish moisture within the soil. Another trick you can use is to put the plant on a saucer so that the water that does fall to the bottom stays there long enough for the roots to absorb it.
What to do if your plant is overwatered?
With an over watered plant you have to do pretty much the exact opposite. You’ll need to stop watering the plant and only restart when the top few inches of soil begin to feel dry. If you don’t want to wait for the plant to dry out you can also re-pot the plant into soil of a more appropriate moisture level, this may cause more stress on the plant, however.
For a more in depth guide to watering your plants, check out this article we wrote: The Absolute Best Way To Water Your Houseplants And Promote Strong Root Growth
Is temperature stress turning your ZZ plant leaves yellow?
Another common reason why ZZ plant leaves begin to turn yellow is when the temperature isn’t regulated correctly. This is often always caused by a draught which can bring sudden bursts of cold air multiple times a day. This irregularity in the air temperature will cause your ZZ plant to become stressed and as discussed before, this stress is shown by the leaves turning yellow.
This form of temperature stress is not to be confused with the climate constantly being too cold for a plant. If that were to be the case and your plant is simply not used to the cold environment it is situated in then it is much more likely that the leaves will turn brown and begin to curl up.
What to do if your plant is under temperature stress?
If you believe that your yellowing leaves are caused by temperature stress due to draughts then the simple solution is to move it out of the way of that draught or stop it all together. There is not much more you can do in this case but at least it is a simple and easy fix.
Is a nutrition issue turning your ZZ plant leaves yellow?
Both overfertilizing and underfertilizing can be reasons for why your ZZ plant leaves turn yellow. This stress is much easier to identify because of the pattern that the leaves will show. When a plant is under this sort of stress the leaves will begin to yellow but the veins that go through these leaves will remain green. When you see this you will immediately know what the problem is.
When you overfertilize your plants you’re putting too many chemicals and nutrients into the soil, this will burn the plant as not only will change the pH levels to those that are inappropriate but it can flood the plant with the unnecessary chemicals from fertilizers. This response is seen in the plants leaves turning yellow because even though there are more than enough nutrients available, the plant has no means of absorbing them.
When you underfertilize a plant a similar reaction happens as there is not enough nutrients for the plant to survive, the first part that it will sacrifice are the leaves.
What to do if your plant is underfertilized or overfertilized?
Well, if you think that your plant is underfertilized, the solution is simple, give your plants some fertilizer. Not too much though because you don’t want to overcompensate and burn the plant due to overfertilizing.
If you have overfertilized your plant then there is a few ways you can go about it. You can run your plant under a tap for 30 seconds or so to drain out some of the excess chemicals and nutrients however this isn’t always effecting. The best practice is to re-pot your plant into some soil which is of an appropriate pH level and one that the plant will be able to thrive in. Always when re-potting or moving plants, ensure to water them after as it helps to reduce the stress that they feel.
Is lack of light turning your ZZ plant leaves yellow?
Here is a little science lesson about plants. They get their energy from absorbing sunlight which is done so through a pigment called chlorophyll, which is green in colour and in turn gives leaves their green complexion. When a plant doesn’t receive enough sunlight it decides that there is no use for it to produce as much chlorophyll as it is not being used. Without this green pigment being made the leaves turn yellow. So if your plant is in the shade most of the day or is getting hardly any light at all, yellowing leaves would indicate that the plant needs more sunlight to thrive.
What to do if your plant isn’t getting enough light?
This one is really simple. Open some blinds or move the plant to somewhere that receives more natural sunlight during the day. You will most likely have to find this plant another spot within your house as if you put it back to its original spot the same issue will occur all over again.
Is disease turning your ZZ plant leaves yellow?
This last reason for your ZZ plant’s leaves turning yellow is possibly the most serious and also the hardest to fix. When your plant is stressed the leaves can turn yellow, so when your plant is being attacked of course it is going to be stressed. However disease an cause your plant to not absorb water or nutrients correctly, it may also halt the production of chlorophyll. Almost all of the above mentioned reasons for your plant’s leaves turning yellow can be caused because of diseases.
Bacterial or fungal infections are most common in ZZ plant and can be brought on by poor soil maintenance or by introducing the disease into your home through the purchase of a new plant or use of new potting mix. You’ll know if it is a disease which is causing your plant’s leaves to turn yellow because there will be other signs of stress on the plant such as darkened or black stems, black spots on the plant, wilting and discolouration elsewhere in the plant.
What to do if your plant is being attacked by a disease?
Firstly you’ll need to identify what is affecting the plant, this can be done by a detailed google search, alternatively you could take a picture of your ZZ plant or take the plant itself to your local garden centre and they should be able to help identify what is going on. They can also recommend treatments to fix the issue. Common treatments include pesticides and soil drenches.
So as you can see, there is no reason for you to stress just because your plants are stressed, with a bit of patience and often some minor changes to how you care for them you will be able to get them to tip top shape in no time! Whether it is an issue with moisture, temperature, nutrition, light or disease, all can be easily managed and your plant will thank you for it!