Caring for any plant can be a challenge, but orchids are infamous for being delicate, tricky to grow, and yet still very desirable to have in the home. However, when you run into problems, it can be highly frustrating, and not always have an obvious solution that will overcome the issue. So, how do you deal with orchid leaves turning yellow? (Prevention, symptoms, and fixes)
There are several reasons that orchid leaves turn yellow, such as too much light, too much or too little water, temperature problems, excess nutrients, or diseases. Fortunately, most of these can be fixed once you’ve diagnosed the issue and corrected it.
How Can I Prevent Yellow Orchid Leaves?
We all know that prevention is better than cure, and if you want to prevent yellow orchid leaves, you need to meet your orchid’s needs as much as you possibly can. There are quite a few things involved in orchid care, and like all plants, they have specific requirements that must be met for them to stay healthy.
So, how can you keep orchids happy? Let’s look at common issues that cause them to turn yellow so you know how to avoid these problems.
Too Much Direct Light
This is one of the commonest issues that orchids suffer from, and if you’ve got orchids in your home, you have probably encountered this issue at least once.
You should be able to tell this apart from other yellowing issues because the yellowing is likely to be nearest the strong light, usually on the tops of the leaves and the parts that are getting the most sun exposure.
It can be difficult to get the right amount of light for your orchid because orchids grow in slightly unusual conditions. They are often found near the tree canopy in rainforests, and up there, they get plenty of light, but no direct sun at all – because it’s all being filtered through a thick layer of tree leaves.
Therefore, in your home, they need bright but indirect sunlight. They don’t like to be kept in the dark and they won’t tolerate a lot of shade, but they also do not enjoy being in direct sunlight. Their leaves can’t cope, and they are likely to burn or turn yellow.
The solution to this is to ensure that your orchid is never in direct sunlight. If you have a windowsill that faces east or west, this may be a suitable place to put the plant, or you might be able to put up a shade so that your plant is protected from full sun.
If your orchid’s leaves have turned yellow due to too much sun, make sure you move it quickly because it will keep getting worse. You should place your orchid further away from the window, or hang a thin curtain between your orchid and the glass. This will help to reduce the sunlight and let your plant’s leaves heal.
Too Much Water
Orchids are unfortunately very prone to over-watering. Many orchids are epiphytes, and this means that they grow on tree branches, rather than in the soil. This means that they don’t usually have soil trapping moisture around their roots, and instead, water runs freely over their roots and dries off them quickly.
The roots are designed to absorb moisture when it is available and hold onto it even when the surroundings dry out, and that means that if there is also a lot of moisture available in the environment, the plants are very likely to end up with too much to drink.
Too much water around the roots often leads to rotting, and this will quickly make your plant sick. You need to water your orchid less frequently than most people think. It is a good idea to keep orchids in a very well-draining growing medium and to always check whether they need a drink before you give them one.
To check this, press your finger into the top inch of the soil or orchid bark, and see if it feels moist. If there is any dampness, the orchid does not yet need more water. If the growing medium is completely dry, you may be able to water the plant, but don’t rush to.
On the whole, orchids will be far more tolerant of dry conditions than wet ones, and root rot can kill a plant very quickly, so err on the side of too little to drink, rather than too much. Remember that in the winter, orchids will need less water than they do in the summer, and adjust your approach accordingly.
The Wrong Temperature
Orchids prefer to be kept at around 60 – 80°F, and this is usually the temperature range your home will fall into. However, if your orchid gets overheated or chilled for any reason, you are likely to see yellowing in its leaves and it will often seem limp and sad. It may lose leaves, and could even die if the temperature stress is excessive.
You can also look out for things that might cause an abrupt temperature change, and this is something that you should think about when situating your plant. If you are putting it on a windowsill, does the window get very hot in the summer, or very cold in the winter?
Is there a strong draft from a cold vent nearby, or do you have a radiator right beside the orchid? Any of these things could cause temperature stress and a sick plant will struggle to recover, especially if the stress continues.
You need to take prompt action to remove the source of the temperature change or – probably easier – move your plant to a different spot. It may take some time for the leaves to return to their normal green, but once your plant’s temperature has stabilized, it should be happier.
Don’t leave orchids outside in the middle of summer or as winter is approaching unless you are in a region where the temperature will not dip below or rise above the range that they can tolerate. It is important to protect them from sudden fluctuations even if these are within the range they can tolerate.
The Wrong Amount Of Food
It’s also very easy to over-feed an orchid, and if you have done this, you’re likely to see yellow leaves as a result. Often, over-feeding is a result of being too eager to care for your plant and getting carried away, but unfortunately, it will make your orchid sick.
Nutrients will build up around the roots of the orchid, clogging up the soil or bark and overwhelming the roots. Any plant that is fed too much will suffer, and orchids are no exception to this general rule.
You can’t easily fix over-feeding, although you may find that re-potting your orchid in a fresh potting medium and gently rinsing its roots will help. As with other plants, you may be able to flush the excess nutrients out of the soil, but you do need to make sure the plant dries out reasonably quickly, or you’ll be looking at an over-watering problem next.
Of course, you can also under-feed orchids, although they aren’t considered heavy feeders so this tends to be a bit less of a problem on the whole. You should be feeding them relatively rarely, with diluted fertilizer. Follow the guides on the bottle, but you may wish to dilute to about half strength or nearly half to stop the fertilizer from burning your plant’s roots.
The best way you can avoid leaf yellowing from either over-feeding or under-feeding is to establish a regular feeding routine. Find guides for your specific variety of orchids and stick to these, setting yourself reminders throughout the year, as they will vary depending on the season and state of your orchid.
A flowering orchid should not be fed, so when your orchid is blooming, stop fertilizing it. It won’t hurt it, but it also won’t do it any good.
As with water, too little food is often better than too much, so don’t overwhelm your plant with fertilizer. However, iron deficiency can show through yellow leaves, so if you haven’t fed your orchid for a while and you can’t find another cause, it is probably safe to assume it should be given some food.
There are a lot of plants that don’t tolerate tap water well, and unfortunately, orchids are among them. If your water is hard, it has a lot of lime in it, and this will build up in your plant’s container and coat its roots.
Covered in the chalky substance, the roots will be incapable of taking up nutrients and water effectively, and the plant’s leaves will yellow from thirst, hunger, or both. You need to avoid letting your plant get covered in limescale.
That means watering your orchid with rainwater if possible. This will also lack the chlorine found in tap water, which some plants dislike too, so that’s a secondary advantage. Using rainwater will provide some trace nutrients to your orchid and keep it healthier.
If you can’t always get rainwater, don’t panic. Using tap water on occasion shouldn’t be enough to cause your orchid’s leaves to yellow, but it is a good idea to use rainwater or softened water as much as possible.
For those instances in which you do need to use tap water, try to let it stand for a while, as the chlorine will evaporate off. This makes it better for your plant overall, although the limescale will remain a problem.
Fungal Leaf Spot
If the yellowing starts on the bottom or underside of your orchid’s leaves and seems to be spreading, then the most likely explanation is that your orchid has unfortunately contracted fungal leaf spot. This disease needs prompt action. If you don’t treat it, the yellow spots will grow and turn brown.
You should address this first by removing all infected foliage. Take a pair of sharp scissors and sterilize them before carefully cutting away and discarding the yellowed leaves. You may wish to sterilize the scissors in between cuts to minimize the chances of transferring the fungus to the healthy parts of the plant.
Wash your hands thoroughly after handling the plant, and discard the foliage. You may also want to isolate the infected plant from any others to reduce the chance of its disease spreading.
It may be a good idea to treat the healthy leaves and the stems with a mild fungicide to protect them from infection and remove any spores that have spread. Keep an eye on the plant to make sure you have properly addressed the issue.
This is a disease that can affect your orchid if you over-water it, and it is unfortunately very common among orchids. As mentioned earlier, it will cause yellowing in the leaves. If your orchid is looking sick and you don’t know why gently remove it from its pot and check its roots.
If they are mushy or brown, the chances are that your orchid has root rot. This is a disease that will often kill your plant, but if you act quickly, you may be able to save it.
You will need to look at how much healthy root is left. If most of the root mass is gone, saving your orchid is going to be very difficult, but if you have been quick enough and noticed early, you might be able to help the plant.
Take some sharp, sterile scissors and cut away all of the rotting roots. Leave only healthy root, and then gently rinse and allow it to dry out a bit before re-potting. You should put your orchid in an entirely new growing medium, and treat it very gently for a while.
If you are lucky, it should recover and start to grow new green foliage, but this is not guaranteed and will depend heavily on how quickly you have noticed and how strong the plant is.
Root rot is generally a sign you have over-watered your plant, so remember to pare back your watering in the future and always check if the growing medium is dry before you give the plant more to drink.
Bacterial Brown Spot
Spots that are brown or yellow and look somewhat damp are likely to be brown spot. This is particularly common for orchids that are kept in humid, still conditions. Although orchids like humidity, it leaves them vulnerable to attack by fungi.
As with other fungal infections, prompt action is needed to save the plant. Use sterile scissors to remove all affected growth, and treat the remaining foliage with fungicide. You should isolate the plant until you are sure you have dealt with the infection.
This fungus needs somewhat damp conditions to thrive, so it is also a good idea to let your orchid dry out a bit. Make sure that the unaffected leaves are not wet, and avoid misting your plant for a while. This will make it harder for the fungus to spread and keep multiplying.
Natural Foliage Death
Of course, there are many points at which a plant’s leaves turn yellow and drop off even without any mistakes being made – simply because the foliage is old. You may observe this occurring on your orchid from time to time.
That means that when you first spot a yellowed leaf, you shouldn’t panic, even if it is followed by a second, as long as these are old leaves. There is nothing wrong; the plant is simply cutting off the energy supply to these leaves so it can redirect its resources into new, young growth.
The leaf should gradually get yellower and shrivel, but as long as this is in the context of healthy new growth and no yellowing in the young leaves, it is not something that should concern you.
After a while, the leaf will drop off on its own. Many people remove the leaves to try and get their plant to focus on the new, young growth, and to make their orchids look prettier, but this isn’t necessary.
Cutting your plant when you don’t need to makes it more vulnerable to infection and disease, so it’s better to avoid this if possible. If you do feel you need to remove the leaves for some reason, make sure that you use sterile scissors to give a clean, neat cut. Don’t snap the leaves off or tear them away, as this will damage the plant.
If you have recently moved your orchid from one room to another or you have just brought a new orchid into your home, it is safe to assume that your plant will feel some stress. Plants need time to adapt to a new environment, just like people do.
Your plant may show its stress by yellowing, so if you have recently moved it from one spot to another, moved house, or just brought a new plant home and it’s starting to look a little sickly, you shouldn’t be too concerned.
You can’t really do much about this sort of leaf yellowing because you can’t stop your plant from being stressed by changes. All you can do is wait for the plant to adjust to the new environment and recover, and soon, it should have fresh green leaves to replace the yellowed ones.
The only thing you can do about stress is avoid moving your plant as much as possible. If you don’t have to relocate your orchid, don’t do so – but if you do, don’t worry too much. It will adjust and recover.
The Environment Is Too Dry Or Too Wet
Sometimes, yellow and crispy leaves might indicate that the orchid’s environment is too dry. Remember, orchids come from humid environments. They thrive in rainforests, and they, therefore, like the air to be wet.
This is quite hard to replicate in a home, but you do need to pay attention to the humidity levels around your orchid.
Equally, however, orchids can end up too wet, and this leaves them vulnerable to fungal infections, especially when they are also warm – as they are likely to be within a home. This, as we have already discussed, will also lead to yellow leaves and rotting.
Striking a balance in which your orchid is humid enough but not so wet it is at risk of rotting is a challenge. You might want to buy a hydrometer so you can always check whether your orchid needs humidity.
If you do need to humidify your orchid, you can do so fairly easily. Either buy a plug-in humidifier or a spray bottle. You can then gently mist your orchid whenever the hygrometer tells you that its environment is getting a little dry, and hold off on misting it when conditions are wetter.
Another good alternative is to make a humidifying tray. This will provide passive humidity to your plant and can be used whenever you want it. To make one, simply get a plant tray with no holes in it, and fill the bottom with gravel or small pebbles.
Add water to the tray, but make sure its surface stays below the level of the pebbles. You can then stand the orchid’s pot on these stones, and the water will slowly evaporate, misting the leaves as it does. This gives your orchid humidity when the weather is dry, and you can simply move the plant off the tray when you don’t want to humidify it.
You may also wish to use a fan or open a window near your orchid on some days. This will help to replicate the somewhat windy conditions in the canopy of a rainforest and will make your plant less vulnerable to mold and fungi.
Many orchids like humidity levels between 40% and 70%, but it’s a good idea to check what your specific variety prefers.
Orchid leaves can turn yellow for several different reasons, but hopefully, you now have a good understanding of the symptoms you may see and possible ways to fix issues. On the whole, you should pay attention to leaf color as yellowing can indicate serious problems with the plant, and you may need to intervene.