Although ZZ plants are probably the best indoor plants for beginners because they require little maintenance and can thrive in a variety of environments, if they are neglected or given poor care, their leaves may eventually turn yellow.
The main cause of yellowing leaves in ZZ plants is overwatering, which results in root rot. Yellowing leaves can, however, also be a sign of underwatering and, less frequently, of temperature, light, fertilization, etc.
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Why Are My ZZ Plant’s Leaves Turning Yellow?
Overexposure To Direct Sunlight
To grow happily and healthily, ZZ plants prefer low-to-moderate light. They are ideal indoor plants for dim environments due to their low light requirements. The burning and yellowing of leaves could result from exposing them to the sweltering sun.
Here’s how to diagnose if the yellow leaves are caused by overexposure to sunlight:
- Examine the leaves for sunburn spots
2. Transfer the plant to a dimly lit location. Cover the window with blinds or sheer curtains to prevent direct sunlight if it’s next to an east-facing window.
3. If it’s an outdoor ZZ, move it under a structure that provides shade, such as your patio or a tree.
Insufficient Light
ZZ plants don’t require a lot of light; they thrive away from windows. But they still require SOME light.
The leaves will begin to drop and turn yellow if your plant doesn’t receive enough light. Older leaves near the plant’s base are particularly susceptible to this.
Putting your plant in a brighter area of the room will help. It’ll be a lot happier.
Salt Burn From Overfertilization
Yellow leaves can result from nutrient imbalances brought on by under-fertilizing or overfertilizing your ZZ plant. During the plant’s growing season (between April and August), it is necessary to feed it once a month with a diluted water-soluble fertilizer.
Overfertilization is when you apply fertilizer more than once per month. Burns can be easily caused by too much salt.
When you fertilize a plant insufficiently, you may only do so once a year or not at all. However, ZZ plants can endure in nutrient-poor soils. The nutrient shortage is unlikely, even if you haven’t used fertilizer.
However, when it does, it might result in yellow foliage.
Pest Infestation
Insect infestations are more likely to affect ZZ Plants that are weak or stressed. Spider mites and other insects that feed on plant sap can dehydrate your plant. Leaflets and fronds start to yellow, which is a problem that shows up quickly. In an indoor environment, scale, mealybugs, and spider mites are frequently present. These tiny pests multiply and spread throughout leaves, fronds, and crevices if they are not eradicated quickly. In particular, if your ZZ is already unwell due to nutrient deficiency or improper soil moisture, the insects’ piercing mouths exhaust your plant and hasten to yellow.
Overwatering
Inadequate watering is the main reason why the ZZ plant leaves yellow.
One of the most frequent reasons for the yellowing of the ZZ plant’s leaves is overwatering. Before rewatering, you must give the soil a little time to dry out. Typically, you should water no more frequently than twice a month. You run the risk of developing root rot if your soil is perpetually moist or damp.
Your plant is probably in a pot that is too big for it or the soil isn’t draining well if, after two weeks of watering, the soil is still wet or damp. Consider moving your plants into a smaller pot.
Carefully remove your ZZ plant from the pot and look at the roots if you notice that many of the leaves are yellowing and the stalks are drooping.
Root rot should be simple to identify because the roots will be mushy, darker, and possibly smell bad. Dig up the surrounding soil and remove any damaged roots. You can keep the soil around healthy roots if the damage is limited to a small area.
If the root system is too severely damaged, dig up the soil, scrub the roots, and then replant your ZZ plant. If the harm was not too severe, it ought to recover.
If there are signs of root rot and the soil is still drenched in moisture, you will also need to repot the plant into the new soil. more so if your soil is poorly draining.
In the future, cut back on your watering frequency.
Too Little Water Is An Issue Too
ZZ plants are said to benefit from neglect in many care manuals. It’s simple to misinterpret this, though. You shouldn’t completely disregard your plant just because it has been neglected. Just slightly less than many other houseplants, it requires regular watering to thrive. The leaves of your ZZ plant may start to turn yellow if the soil is frequently allowed to dry out and you don’t water it for several weeks or even months.
Low Humidity
Although I find leaf drop to be much less common than overwatering, low humidity can still cause leaf drop. The leaves typically develop crispy, brown spots (often on the tips). The leaves may then turn yellow at that point.
These symptoms point to the plant’s drying out. Misting the leaves can help increase air humidity if the plant is receiving adequate water.
Mechanical Damage
This plant has relatively delicate leaves. If you notice a strange leaf turning yellow, it might be because you or someone else recently brushed against it because a leaf can be snapped off with little force.
The leaf began to yellow if the base of the leaf had enough damage to cut off nutrients.
Old Age
It is normal for some older leaves to turn yellow and drop off as plants age, making room for new growth. Some plants choose to devote their energy to growing new plants instead of spending it on maintaining their leaves.
If this is the case, only the older leaves—those closest to the plant’s base—will be yellow; no new growth will appear.
How To Treat Zz Plants With Yellow Leaves
The ZZ plant must be immediately removed from too-wet soil, even though repotting is typically done in the spring. Remove your Zamioculcas from the pot and inspect the roots for damage. Remove anything that is soft, brown, and rotten. The remainder of the plant can now be repotted in new soil. Use dry soil, and add about a third of the sand to the mixture. So, water can drain better and the substrate becomes more permeable. In order to give your ZZ plant’s roots time to heal, you should stop watering it for at least a week. Even after that, use water sparingly. The plant can also be relocated to a more sunny area for a quicker recovery.
Remedies for root rot on Zamioculcas:
- Remove the plant from the pot
- Investigate root balls for brown or soggy roots
- Remove affected parts of the root
- Mix dry soil with one-third sand
- Repot the plant in fresh substrate
- Do not water for some time
- Place the plant in a brighter place
- Watering more sparingly in the future than before
Frequently Asked Questions
Does Yellow Zz Leaves Ever Revert To Green?
ZZ has a reputation for being low maintenance and enduring neglect. But yellowing leaves are a sign of continued neglect and poor growing conditions. After determining and addressing the true cause of yellowing, your ZZ can once again turn green. The best next step would be to create an environment where the plant can flourish.
This plant’s ideal conditions include:
- Low-to-moderate light, not direct sunlight exposure
- a deep watering every two weeks in the summer and every three weeks in the winter. Prior to watering, the soil must be completely dry. Avoid letting it stand in water.
- They prefer temperatures ranging between 65 °F and 85 °F
Why Are My Zz Plant’s Leaves Fading To Brown?
Plants with brown, crispy leaves are a sign of inadequate moisture, low humidity, or too much sunlight.
What Is Causing The Black Spots On The Yellowing Leaves Of My Zz Plant?
You’ve severely overwatered your plant if its leaves are yellow with black spots. Report them in a container with drainage holes after removing them from the pot, dumping any excess soil, and adding fresh, dry potting soil. Only water your plant when the soil is visibly dry.