Yellow leaves on a plant can look beautiful, and I’m embarrassed by the number of times I’ve thought ‘wow, look how pretty tha-‘ and then the leaf drops off.
First things first – don’t panic when you see a yellow leaf. Your plant is not necessarily dying. But this does need to be said:
A yellow leaf on a house plant is unlikely to turn green again UNLESS the yellowing is caused by a nutritional deficiency, which if rectified, could cause the green colour to return.
Usually though, say goodbye to the green. Hell, make your peace and put the whole leaf’s affairs in order. Never mind. (Hopefully) there are plenty more where that came from.
What causes a plant’s leaves to turn yellow?
This is the biggest cause of yellowing leaves, and it’s super common. Yellow leaves are a sign of stress, and the stressor is likely water.
If you have a lot of yellow leaves, you may be dealing with root rot, in which case, you may need to repot. If you’re a serial over waterer, I have a post on how to stop overwatering your plants, and also one on how long it takes for a plant to recover from overwatering.
If the leaf turned yellow due to overwatering, it’s highly unlikely that the leaf will turn green again. Sorry.
Confusing, isn’t it? Underwatered leaves may go yellow on their way to going brown, but whether you’re under or overwatering moisture-stressed leaves are unlikely to go green again.
The leaf is old
If the leaf is small, and near the bottom of the plant, it may just be old.
If you only have dramatically yellowing leaf and the rest of the plant is growing healthily, then it’s probably just that leaf’s time.
There’s nothing you can do about this. It’s just part of the plant’s natural life cycle. If it looks unsightly, then snip off the leaf with sterilised scissors. Decaying mater can attract pests like fungus gnats, so it’s a good idea to remove it as soon as it looks a bit gross.
Again, your leaf ain’t turning green again. If you’re lucky, you’ll get autumnal colours, which are beautiful, albeit a bit sad. Alocasia Amazonica leaves look incredible on their way out.
A nutritional deficiency
If the old leaves are yellowing, and the new leaves, are pale, you may be looking at a nitrogen deficiency. Either go with a general plant fertiliser (check out my resources page for my recommendations) OR you can DIY it and add some coffee grounds to your soil.
You MAY have some luck with turning leaves back from yellow to green, but don’t be surprised if you lose the more yellow leaves
Lack of light
Light is plant food, in simple terms. If they’re not getting enough, then they can start to produce, leggy, yellow growth. The solution is to either move your plant to a brighter spot, clean your window, clean your plant, or add a grow light – the one I use is on my resources page.
Lack of humidity
Lack of humidity usually manifests itself as crispy leaf edges, but you could notice some yellowing first. If you’re quick to add humidity. you may be able to stop the brown edges, but you’re unlikely to be able to turn the leaf green again. I assume the cells close themselves off to chlorophyll.
If you see this happening, you need to act fast. You can use a pebble tray or just a pot of water as a quick fix, but you need to either get a humidifier or move the plant into a more humid room.
Don’t mist your plant – misting can attract fungus and pests, and your plant may be in a weakened state. We don’t want a yellow leaf situation to turn into a full-on infestation.
How can you prevent yellow leaves?
Obviously there’s not a lot you can do about your plant’s natural life cycle – some leaves will turn yellow, die, and drop on. Tis nature. Tis beautiful. Deal with it.
The rest of it is just down to good plant husbandry. Keep your plant strong and healthy. Here are a few tips to do just that:
- Use a moisture metre, so that you only water your plant when it needs it
- Check your plants over AT LEAST once a week, preferably twice, so that any problems can be identified and dealt with quickly
- Water your plants with room temperature water. Either leave it out overnight or add a bit of hot water in
- Make sure your plants are getting the right amount of light and humidity. Add grow lights and humidifiers if necessary, but closing doors and cleaning windows goes a surprisingly long way
- Keep your plants dust-free by regularly wiping them with a cloth dipped in a neem oil and warm water solution.
How can I tell if the leaf is old, or if the plant is dying?
This can be a tricky one, because a yellow leaf that’s yellow because it’s old is still as yellow as a leaf that’s overwatered. There are a couple of things to watch out for though.
- Old leaves tend to be near the bottom of the plant, and are often smaller
- That being said, water-stressed plants may sacrifice their older leaves, so never just assume it’s an old leaf.
- A big leaf dying is sometimes a sign of water stress
- The colours on an old leaf tend to be deeper – going from yellow to orange, to brown.
I know, I know. It if was easy we’d all live in jungles though.
The best advice I can give you is to observe your plants.
Signs of water stress usually affect the whole plant, but if you see yellow leaves, keep a close eye until you’re sure it’s just a case of old age.
If I find the cause of the yellowing leaves, will they go green again?
Errrr, probably not. I’m not going to say definitely not, because if you catch it early enough, you may be able to get some chlorophyll back into the leaf. Chances are though, your plant has already written that leaf off.
In some cases of nitrogen deficiency, you can reverse the damage, but it’s unlikely that you’d catch it early enough.
You can, however, prevent any further yellowing by identifying the issue and rectifying it. Your plant wants to get better, you just have to help it.
By the way, some plants put out yellow leaves at a rate of knots. I have two Philodendron Selloum which ALWAYS have at least one yellowing leaf. They’re perfectly healthy, and are putting out new growth, but they’re always sacrificing one leaf or another. Has anyone else experienced the same?
I’m not sure if it’s to do with the type of plant because they both had a hairy start in life. One was from a big supermarket and was wrapped in plastic and sat in a draft, and the other I bought from Wilko. As an outside plant. It was outside. In England in October. The poor lamb.