Caring for plants is generally enjoyable, but it can be challenging, especially when something goes wrong and you aren’t sure how to go about fixing it. At this point, it often becomes frustrating, so today, we’re going to look at why Anthurium leaves turn yellow and how to fix it.
Many things can cause yellowing in the leaves of these beautiful plants, including temperature stress, watering problems, lack of nutrients, too much sunlight, low humidity, old age, and too much fertilizer. You will need to accurately identify the issue in order to fix it and restore your plant to full health.
Reason One: Temperature Stress
Like many tropical plants, Anthuriums like stable, warm temperatures, and they will not be happy if temperatures drop too low, or if they constantly fluctuate, going from warm to cold and back again.
Unless you live in a tropical climate, the environment outside your home will often be too cold for an Anthurium, and you will need to protect it by keeping it in a stable, warm environment. The home works well for this, but you should be aware of breezes and chills.
If you put your Anthurium close to a fan or air conditioner, for example, it is likely to struggle. If you put it near a heater, despite its love of warmth, it will almost certainly die, because radiators are far too hot even for an Anthurium.
Your plant will respond to temperature stress with yellowing leaves, and this is one of the first issues that you should check for, especially if you have recently moved your plant or the seasons are changing.
How To Fix It
The easiest way to avoid temperature stress for an Anthurium is to get a thermometer so that you can check the temperature at any given time. It prefers a temperature range between 65 and 80 degrees F during the day, although it will tolerate temperatures down to 60 degrees F at night.
When choosing where to put your plant, mentally mark off heaters and vents, and ensure that it is not within a few feet of these. Particularly drafty windows or external doors could also be dangerous, especially in the winter.
Try to put your Anthurium somewhere stable, with no external doors, to reduce the risk of temperature stress. Its leaves may turn back to green once the source of stress is removed, and new growth should be green.
Reason Two: Too Little Water
Like most plants, Anthuriums take in nutrients at the same time as water, so if they don’t get enough to drink, they will not have everything they need to make strong, green foliage. They will also likely be stressed, which can cause leaf yellowing.
Check whether it needs a drink before you do much else. Press your finger into the surface of the soil to about an inch or two inches down. If the soil feels dry, your plant is thirsty.
Anthuriums will also wilt when they aren’t getting enough water, with their beautiful leaves turning floppy and limp. They are from naturally damp environments and dislike being dried out.
How To Fix It
The obvious fix here is to give your plant some water, but you may need to go a little further than that. If it is really dry, try standing it in a sink or a shower, and run some water through the pot and into the sink.
Leave the plant there for about ten minutes so that the soil gets thoroughly saturated, and then allow it to drain and put it back in its usual position. It won’t need a drink again for a while, but be careful not to let it dry out again.
You may wish to set reminders on your phone if you struggle to water your plants regularly. However, you shouldn’t remind yourself to blindly water, or you can cause more problems than you solve. Instead, remind yourself to check whether your plant needs a drink by pressing your finger into the surface of the soil and checking how dry it is.
Only give it a drink if the soil has dried out, or you will cause other problems.
Reason Three: Too Much Water
Unfortunately, over-watering is an extremely common issue for many plant owners, and it’s probably the top cause of yellow leaves among Anthuriums. Owners worry that their plants aren’t getting enough to drink, know that Anthuriums prefer wet environments, and therefore go too far.
This can be dangerous to your plant’s health for several reasons. Firstly, plants absorb oxygen through their roots, but they can’t do this if the roots are permanently submerged in water. This will cause stress.
Secondly, over-watering will put your plant at risk of root rot if the problem continues – which we are going to look at next. If you stop over-watering your plant quickly, you may not have to deal with root rot.
How To Fix It
The first thing to do is to stop watering your plant and to tip out any excess water that is standing in its drip tray so that it can dry.
If it’s possible to increase the airflow in the room without exposing your plant to drafts, do so; circulating air will help to dry the pot out. Slightly increasing the temperature may also help, but you need to be careful you don’t cause temperature stress.
Next, check what caused the over-watering. Does the plant pot have sufficient drainage holes? Are you using the right kind of soil for an Anthurium? Are you just following your watering routine too religiously?
Take action to resolve whatever problems you find. This may mean repotting your Anthurium into a more suitable container, using a more suitable growing medium. It might mean being stricter about checking whether your plant actually needs a drink before you supply one.
Try to reduce the risk of over-watering happening again in the future if this is a potential problem because it stresses your plant out and will slow down its growth.
Reason Four: Root Rot
Over-watering can also lead to root rot, which is a serious issue that will kill your plant fast if you don’t take action. Root rot means the plant’s roots are being eaten by a fungus (there are many different types), and this prevents them from absorbing water and nutrients. It occurs when your plant’s roots stay wet for too long.
The roots will no longer be able to function properly, and this will result in a plant that is starved of oxygen, nutrients, and water – even though it is sitting in water and appears to have enough to drink. If you think your plant has root rot, you will need to take action to solve the problem, because it will not solve itself.
It is crucial that you act quickly, too; root rot can kill a plant in a few days or weeks. Taking immediate action may save it, but letting the problem persist for a while will result in the plant’s death.
Many people discard plants with root rot because they can be hard to save, but if you would rather not do that, you may still be able to rescue your Anthurium.
How To Fix It
Firstly, spread some newspaper out on a surface and get ready to repot your plant. You may wish to move your Anthurium into a new container if you recognize that its current pot has poor drainage, or is getting too small. You can keep it in the same container if it is still suitable.
Get some fresh potting medium ready. Make sure there is plenty of good drainage material mixed in to minimize the risk of root rot happening again. Adding gravel or perlite to the mix may help.
When you are ready, tip your Anthurium out of its container, supporting the leaves with your other hand so that they don’t get damaged. Brush or wash the remaining soil off its roots so that they are clean, and then inspect them.
Root rot will cause the plant’s roots to turn dark and mushy, whereas they should be firm and pale brown or cream. Touching the roots will help you establish whether the cells have started breaking down.
If you are right that your plant has root rot, you need to get rid of as much of the damaged matter as possible. Take some sterile scissors and cut away the rotten roots, sterilizing your scissors repeatedly as you work to avoid spreading the fungus to the roots that are still healthy.
Remove all of the damaged roots, but leave any firm, cream roots intact. If a lot of roots have to be removed, be aware that your plant may not survive.
Next, use some clean paper towels to pat the remaining roots dry, and soak as much moisture as you can out of them. You can leave your Anthurium to dry in the air for a few hours, as this will also help to combat the moisture issue.
When its roots are as dry as you can reasonably get them, repot the Anthurium in some clean, fresh growing medium. Do not use any of the old medium. If you are going to reuse the container, give it a good scrub with hot, soapy water first to remove any remnants of the fungus.
When your Anthurium is in its new container, put it in bright, indirect light and treat it very gently for a few weeks. Its chances of recovery will depend on how advanced the root rot was, but if you had to cut off a lot of roots, you may not be able to save it. With any luck, it will start growing new roots and recovering after a few days.
Reason Five: Too Much Sun
Your Anthurium will not like direct sunlight. Many new growers try to maximize the light that their tropical plants get because they come from hot countries with lots of bright sun – but this isn’t actually helpful in many cases.
A lot of these plants grow in rainforests, under thick canopies of leaves. They do like to have lots of light, but they don’t deal well with bright sunlight falling on their foliage. If your Anthurium is too close to the window, it may be turning yellow because it’s getting too much light and this is causing stress.
How To Fix It
You can either relocate your plant or shield it from some of the sun, especially at midday. Relocating it will be the better option if you have a more suitable spot for the plant, but if you don’t, consider putting up a thin curtain.
This can be tricky because your Anthurium does need plenty of light so that it can photosynthesize and grow. It won’t like being plunged into darkness. Try a thin curtain or even a net one, depending on how strong the sun is, and draw it back out of the way when the sun is weaker.
If this doesn’t seem to help, see if you can move your plant further from the window. The rays of light will be at their most intense right beside the glass, so the difference of a few feet can keep your plant from being stressed by the sun.
Reason Six: Low Humidity
Sometimes, Anthuriums will start to yellow because the humidity level is too low for them. They prefer humidity levels to be at 50 percent at least, preferably higher, and will suffer if they are notably lower than this.
Most homes are too dry for Anthuriums, and this can cause stress. It is often a bigger problem in the winter, when the air is cold and dry, and we have our heating systems on, making the air drier than ever.
If your Anthuriums leaves are yellowing even though you are watering it well, consider whether your home could be too dry for it.
How To Fix It
You could move your Anthurium into your bathroom, where it will enjoy the humidity from showers and baths and running water. Alternatively, try leaving the bathroom door open after a shower, and see if this helps.
If that isn’t practical or doesn’t seem to be sufficient, consider getting a plant sprayer. You can lightly mist your Anthurium’s leaves and soil a few times a week, preferably in the morning. This will increase the humidity directly around the plant, for a short period tough, but may help it to perk up.
If your schedule is too busy to allow for this, you may try a plug-in humidifier. However, also make sure that you aren’t humidifying your plant too much; give it a chance to dry out occasionally, or it may become vulnerable to fungal infections.
If you mist your plant manually, aim to do so in the early part of the day. If you are using a humidifier don’t forget to switch it off in the afternoon. This reduces the risk of fungal infections, which tend to be more prevalent during the cooler temperatures of the night.
Reason Seven: Natural Aging
Sometimes, a leaf will yellow simply because that particular piece of foliage is old. When foliage is old, the plant cuts off the resources being sent to that leaf so it can focus on creating and maintaining new growth instead.
This will cause the leaf to yellow because it no longer has the nutrients needed to maintain its fresh, green appearance. This can happen quite gradually, and it may be a long time before the leaf shrivels and drops off.
Usually, only one or two leaves will die of old age at a time, and they will be tougher, older foliage. If you see young growth turning yellow or a lot of leaves yellowing at once, there is another issue at play.
How To Fix It
There isn’t anything that you can do to prevent natural aging; it is a normal part of the plant’s growth. If you like, you can cut off old leaves using sterile shears, so the plant focuses on its other growth.
Reason Eight: Excess Nutrients
If you regularly fertilize your Anthurium, this could be the cause of yellow leaves. Anthuriums do need food, but an overdose of fertilizer will lead to a buildup of salts and nutrients in the soil, and these can burn the plant’s roots and make it unhappy.
How To Fix It
First, try to fertilize on a schedule to avoid this happening, and reduce fertilization when the plant is not actively growing (during the winter). However, if you have over-fertilized your plant, simply place it in the bath or sink and flush its container out with lots of fresh water.
This will rinse the excess salts and nutrients from the soil and should resolve the issue.
Anthurium leaves can turn yellow for a whole host of reasons, so make sure you are taking the time to accurately identify any issues. This will put you in a good position to correct them and restore your plant to full health.