ZZ plants are happy plants most of the time, but they still have their issues occasionally. One of the more common ones being the yellowing of the leaves. So, why does your ZZ plant have yellow leaves? Learn all the potential causes, how to identify what is causing the issue with your plant, and most importantly, how to fix it and avoid it in the future.
As with most plants, yellow-colored leaves are a sign of a leaf struggling or dying. Once the leaf turns completely yellow, it will eventually die and fall off. This can be a part of the leaf’s natural life cycle or a sign of an underlying issue – sometimes a serious one.
Whenever you spot a yellow leaf on a plant that doesn’t naturally have yellow leaves, you should check the plant if it is doing OK otherwise and rule out any care issues or conditions being off.
Why Does Your ZZ Plant Have Yellow Leaves?
With proper ZZ plant care, you shouldn’t see yellow leaves very often. There are a few things that can cause this, so let’s get through them and get to the bottom of this.
ZZ Plant Has Yellow Leaves at the Bottom
As the plant ages, you can notice an occasional yellow leaf, usually at the bottom. With time, you may even see a whole stalk with all the attached foliage turn yellow as part of the aging process.
If the plant is otherwise healthy, the yellowing doesn’t “spread,” there was or is new growth on the plant, and you don’t feel anything else could be causing this, then some yellowing of the ZZ plant leaves is completely normal.
While a couple of yellow leaves at the bottom usually isn’t a cause of concern, keep a close eye on the plant to see if this persists, and more leaves start yellowing.
Over or Under Watering
The most common cause for yellowing of the ZZ plant leaves is improper watering.
Overwatering is one of the most common causes of the ZZ plant’s leaves turning yellow. You need to let the soil dry a little before watering again. Usually, you should water no more than once every 2 weeks. If your soil is constantly wet or damp, you risk root rot.
If you water your plant and find the soil is still wet or damp after two weeks, your plant is likely in a pot too big for it, or the soil isn’t draining well. You should consider repotting into a smaller pot.
If many of the leaves on your ZZ plant are yellowing and you see the stalks drooping, carefully pull out the plant from the pot and inspect the roots.
Root rot should be easy to spot as the roots will be mushy, darker, and will likely have a foul smell. Remove the damaged roots, remove soil around the affected area. If only a small area is affected, you can leave the soil around healthy roots.
If too much of the root system is affected, remove the soil, clean the roots and plant your ZZ plant into fresh soil. It should bounce back if the damage weren’t too severe.
You will also need to repot the plant into fresh soil if there is a sign of root rot and the soil is still soaking wet. Especially if your soil isn’t well-draining.
Decrease the frequency of watering in the future.
Too Little Water is An Issue Too
Many care guides state that ZZ plants thrive on neglect. However, this can easily be misunderstood. Neglect doesn’t mean you should completely forget about your plant. It needs regular watering to be happy, just less than many other houseplants. If you regularly let your ZZ plant’s soil dry out and do not water it for many weeks or months even, the leaves can start turning yellow.
When you are checking for root rot, there might not be any present. You can, however, spot another issue that can cause your ZZ plant’s leaves to turn yellow. If your plant was happy before and there was lots of new growth, the growth didn’t just happen above the soil. The roots might have gotten too big for the pot, and now your plant is root-bound.
You might even see roots growing above the soil which is a sure sign you should check what is going on under.
If there is no more room for the roots to grow, you will need to repot your plant into a bigger pot.
ZZ plant leaves turning yellow after repotting?
Repotting, while necessary, is stressful for plants. Even if your plant was completely healthy before repotting, it could struggle after you have repotted it.
Some leaf yellowing can be normal, as well as plants looking poorly for a while. The plant should bounce back pretty quickly, though, and the issue shouldn’t progress.
One exception would be if you used soil that retains too much moisture and the soil stays too wet for too long. You should repot your plant again in proper soil.
Repotting a plant into a container that is way too big can also cause issues as the soil will stay wet for longer periods of time.
Plant is Too Dense
If your plant is happily pushing out new growth, things might become too tight, and some stalks can get damaged (literarily squeezed to death).
While pests don’t commonly cause ZZ plants’ leaves to turn yellow, they can damage the leaves enough for this to be the case.
No matter what the cause is, you should always check for and rule out pests.
The leaves on this plant are relatively fragile. Not a lot of force is needed to snap off a leaf, so if you see an odd leaf turning yellow, it could be to you or someone else brushing against it in the recent past.
The base of the leaf could be damaged enough to cut off nutrients, and the leaf started yellowing.
Not Enough Light
If you have your plant in a dark corner and have ruled out every other cause, you might need to move your plant to a brighter location.
ZZ plants tolerate low light pretty well, better than most plants, but there is a limit to that too.
With the ZZ plant, less is more. These don’t need frequent fertilization, and using too much fertilizer can harm the roots. Damaged roots can lead to yellow leaves.
You should fertilize the ZZ plant less than other plants and with half the recommended dosage. If you have been using fertilizer frequently, this might be why your ZZ plant’s leaves are turning yellow.
Flush the soil, let the water gently run through for a minute or so. Avoid fertilizing this season.
Yellow Leaves on New Growth
It is normal for the new leaves to be pale green, but they shouldn’t be yellow.
If other leaves are OK and the new growth is turning yellow one possibility is nutrient deficiency. New leaves are the most sensitive, however you would see yellowing of other leaves over time as well. Lack of iron or potassium are the usual culprits.
Incorrect watering can first show on new growth as well.