Chinese Evergreens (Aglaonema) are stunning houseplants, famed for their diverse and colorful foliage, thanks to the variety of eye-catching cultivars. Whilst generally easy to care for, one common problem is when a Chinese Evergreen gets yellow leaves.
Chinese Evergreens most commonly get yellow leaves due to overwatering, low light, pests, or aging foliage. Yellowing foliage is normally a sign of plant stress unless it affects only a small number of lower leaves. The pattern of yellowing, as well as reviewing the care conditions can help you identify and fix the problem.
This article will help you identify why your Chinese Evergreen has yellow leaves and help you correct the problem and get your plant looking great again.
Watering Problems
Chinese Evergreens are amazing plants. Originating from Southeast Asia, they have been developed into about 25 different cultivated varieties.
If your Chinese Evergreen suffers because of the amount of water it receives, it is highly likely that it is getting too much water rather than too little. Aglaonema plants are best watered once the top 1-2 inches of soil feels dry to the touch.
Symptoms Of An Overwatered Chinese Evergreen And How To Fix It
Look for the following symptoms to identify if your Chinese Evergreen has yellow leaves due to overwatering.
- Drooping foliage, despite wet soil.
- Generally yellowing leaves, often starting with lower leaves first.
- Leaf edema.
- Brown spots of infection on the leaves.
- A rotting smell from the soil – This indicates root rot and needs to be treated immediately.
Any factor that causes the soil to dry out slowly can increase the risk of overwatering. Planting in a pot that is too large, using poorly draining soil, or a pot without drainage holes can cause major problems.
Bear in mind that your Aglaonema will need less water in winter, or when light levels or temperatures are low, due to a reduced growth rate. If you maintain the same watering schedule all year, it is likely you will run into overwatering problems in winter.
If you think your Chinese Evergreen has yellow leaves due to overwatering, check to see if there are any signs of root rot. You can do this by gently removing the plant from the pot temporarily.
If root rot is present, you will need to remove all affected roots and repot the plant in a fresh pot with new, well-draining soil. Read my article on identifying and treating root rot for more info.
If there is no sign of root rot, the best course of action is to allow it to completely dry until the soil around it has no dampness to a depth of around two inches.
You can hasten this process by lessening humidity and moving the plant to a brighter location. Consider whether the plant would be better in a different pot or soil, or whether you need to adjust any other aspects of care.
Yellow Chinese Evergreen Leaves Caused By Underwatering
This issue is easier to identify and much simpler to fix. The yellowing will typically affect lower leaves, as the plant decides to let these die off, favoring younger growth. You will also see brown tips and leaf edges that feel dry and crispy to the touch.
The plant wil usually be drooping and looking quite unwell, nd the soil will feel very dry.
Whilst existing leaf damage cannot be fixed, the plant can usually be saved by resuming a regular watering schedule. If the soil is drying very quickly after watering, consider whether your plant needs repotted, or if the temperature and lighting are too high.
You can read my guide to repotting rootbound houseplants for a step by step guide.
Light
One of the characteristics of Chinese Evergreens that makes them so popular for indoor decorative use is their ability to handle lower light conditions. However, there is some variation in the amount of light these plants require depending on the coloration of their leaves.
Variegated leaves require more light, while purely green or green and white varieties do ok in lower light conditions, even artificial light.
Whilst Aglaonema plants can tolerate low light, they do better in bright, indirect light. In very low light conditions, variegated plants will lose their variegation, while green varieties will initially become more intensely green. If lighting remains very poor, your Chinese Evergreen will develop generally yellow leaves, affecting lower leaves first.
This pattern of change will help you distinguish a lighting issue from an overwatering problem. However, as plants grow very slowly and use less water in low light, they are also at risk of being overwatered.
I’ve written an article about light levels for houseplants which can help make sure you’re giving your plants all the light they need.
The only lighting conditions that Aglaonema plants do not tolerate is direct sunlight (source). When the plants receive too much direct sunlight, the leaves brown and curl as if burned.
Temperature And Drafts
When trying to find out why your Chinese Evergreen has yellow leaves, you should consider temperature and drafts. Prolonged or sudden temperature changes can cause your plant considerable stress and result in leaf yellowing. You may also see wilting, new growth dying and leaf damage including brown edges and tips, and curling
Hot or cold drafts from heaters, air conditioning, or drafty widows are the biggest causes of problems. Take care when positioning your plant to keep it away from all sources of drafts to prevent yellow leaves.
Aside from drafts, your Chinese Evergreen will remain healthy if the temperature does not drop below 55°F (13°C). They can also tolerate temperatures up to 80°F (27°C) with ease. Adverse temperatures or drafts can also result in your plant wilting.
Transplant Stress
Plants experience shock when they are abruptly relocated. This is why uprooting and replanting certain types of ornamental plants should be done with care.
Chinese Evergreens typically stand up well to being repotted, but can develop yellow leaves and wilting if this is not done carefully.
Make sure the new pot is only 1-2 inches bigger than the previous pot, and plant in well-draining soil. A mix of two parts potting soil and one part perlite is a good choice. Read more about choosing soil for houseplants in this article.
You may notice that your plant appears to be rootbound prior to repotting. You may be worried that being rootbound can cause Chinese Evergreens to have yellowing leaves.
Thankfully, they don’t suffer much from being rootbound, so you should really only need to repot every few years, to allow the plant more room to continue growing.
Pests
Insect pests are a danger for virtually all types of houseplants. However, some plants tend to be more susceptible to bugs than others, and some bugs seem to seek out certain types of plants.
If you notice your plant looking sickly, with mottled, yellow leaves, or if there are yellow spots or irregular holes in the leaves, you may have a pest problem.
As it happens, Chinese Evergreens are an attractive target for several tiny predators: aphids, mealy bugs, and spider mites (source). An infestation by any of these three pests can be annoying and even deadly to your Aglaonema.
Therefore, it is important to know how to deal with these little bugs. While aphids are more likely to be found outdoors than inside, they do, on occasion, find their way in and gather on the edges of plant leaves, where they are easily visible as they feast on the plant juices.
Mealybugs look like tiny cotton balls on the stem or leaves of Chinese Evergreens. Usually easy to spot, they will typically only cause major damage to your plant with a bad infestation.
The worst and most common offenders among insect pests are spider mites. These nearly invisible bugs gather first on the bottom of the Aglaonema’s leaves, then migrate over every part of the plant. They reveal their presence through weblike structures.
The yellowing of the Chinese Evergreen’s leaves is a result of the mites sucking away the plant’s internal fluids. Getting rid of these pests requires patience and perseverance, especially with spider mites.
Read my guide to identifying and getting rid of houseplant bugs to get rid of these troublesome pests for good.
Disease Problems
Not only are Chinese Evergreens susceptible to insect pests, but they are also subject to bacterial infection. The most common is Bacterial Blight, a microscopic disease that has followed Aglaonema plants around the world (source).
Bacterial blight causes large, spreading black blotches across the leaves. Affected plants can also develop yellowing of their leaves. Take note that this condition arises almost exclusively in overwatered plants.
You should treat an Aglaonema with Bacterial Blight by isolating it from all your other plants. Remove all affected foliage and dispose of it carefully. Optimize the care conditions for your plant and you may be able to nurse it back to health. If all or most of the foliage is affected, it is better to dispose of the plant and start again with a healthy one.
Fungal infections of Chinese Evergreens are extremely rare. When they do occur, it is, again, invariably the result of overwatering.
Fertilizer Problems
Just as Chinese Evergreens are not needy when it comes to water, they do not need frequent fertilization. Aglaonemas are slow growers anyway, so small doses of liquid fertilizer are adequate.
If your Chinese Evergreen has yellow leaves, there is a small chance it is due to nutrient deficiency, but only if the plant has not been fertilized or repotted for several years.
Nitrogen deficiency will cause generalized yellowing and reduced color in the leaves. Potassium and phosphorus deficiency tend to cause more mottled leaf changes, with brown and yellow discoloration.
If you think fertilizer deficiency is causing your Chinese Evergreen to get yellow leaves, you can solve the problem by resuming a normal fertilizing schedule. The plant should burst into life, with new growth being vibrant and healthy. Damaged foliage may improve a little, but is unlikely to fully recover.
You are much more likely to have problems with your Chinese Evergreen due to over-fertilizing, but these will only cause leaf yellowing in advanced stages when there is root toxicity. You may see salt crusts on top of the soil. In particular, you should avoid fertilizing during late fall and winter. These are the periods of the year in which Chinese Evergreens are not growing strongly, and thus less able to cope with being subjected to overfeeding.
It is not necessary to fertilize these plants more than once or twice a year during their growing season, from mid-spring to late summer. Read my guide to fertilizing houseplants for all the info you’ll need to keep your plants thriving.
Old Foliage
If your Chinese Evergreen has only a few yellow leaves at the bottom of the plant, you can consider this fairly normal. Old leaves will die and be shed by the plant over time, as the plant focuses its energy on new growth.
It is more common to get yellowing leaves in the autumn and winter as light levels decrease and the plant has to make a few sacrifices for the health of the overall plant.
Last Word
If your Chinese Evergreen has yellow leaves, examine your plant closely and think about the care conditions it has been kept in. Overwatering, low light, and pests are the most likely causes of yellow leaves, so investigate for problems here first.
Examine your plant closely, looking for all the available clues that might tell you what the problem is. It’s so much easier to correct the problem when you know what has gone wong.
It’s ok to have a plant that doesn’t look perfect all the time, so don’t worry about the odd yellow leaf here or there. Keep watching your plant closely and notice how the conditions and your care of it impacts the health of the plant.
If you’d like to grow healthy houseplants that thrive year after year, check out my book, Houseplants Made Easy. I cover everything you need to know to become an expert in growing gorgeous indoor plants.