There are eight reasons Monstera deliciosa leaves turn yellow. I only cut them off once they’re completely yellow, to give the plant time to extract all the nutrients.
Overwatering is the most common cause of yellow leaves on Monstera. Old age and pests are the next most likely perpetrators.
- Overwatering
- Old age
- Pests
- Seasonal changes
- Fertilizer issues
- Light issues
- Humidity issues
- Shock
Should I cut the yellow leaves off Monstera?
When Monstera leaves go yellow, the plant is going through the process of senescence – preparing to shed it by sucking all the nutrients out of the leaf.
There’s a great academic paper on senescence here.
If you cut yellow leaves off when there’s still some green, the plant is losing out on nutrients. If your plant is healthy and in good condition, it won’t matter much, but if it’s struggling, give it chance to reclaim its nutrients.
Cut as close to the stem as you can. Any decaying matter can attract gnats.
Are Monstera Thai Constellation more likely to get yellow leaves?
Monstera thai constellation is quite prone to root rot, which is a major cause of yellowing leaves in Monstera. If yours is looking yellow, it’s time to check the roots.
I keep my Thai Constellation hydroponically so that I can keep a close eye on the roots without risking damaging them.
Why do Monstera get yellow leaves?
Root rot
One of the most common reasons your Monstera has yellow leaves is root rot, often caused by overwatering.
As the roots rot, the plant can no longer support as many leaves so it begins the senescence process. As the nutrients are removed from the plant, the leaves start to yellow.
Always check your plant’s roots when you see leaves yellowing. If they’re mushy, you have root rot. Root rot happens when a lack of oxygen to the roots results in a spike in bacteria.
The most common causes of root rot are:
- Watering too frequently
- Using too dense of a potting mix
- Having your plant buried too deep
- Not giving your Monstera enough light
- Too big of a pot
If you suspect this is the cause of your issue, you may find these articles helpful:
- How to help a Monstera recover from root rot
- The best soil for Monstera deliciosa
- When to water Monstera deliciosa
Old age
This is fairly self-explanatory, but, weirdly, there are a couple of different reasons why leaves get old.
The first is that leaves just get old. Usually as Monstera grow, the lower leaves start to die off naturally. They go yellow as the plant removes chlorophyll to redistribute to other leaves.
The other thing that happens is tiny leaves are sacrificed.
Like this:
Look, I know he’s tiny and useless, but he’s cute! Isn’t that something??
This happens a lot in tissue cultured Monstera. Their initial leaves are teeny tiny and young Monstera grow quickly. Once they have a few decent-sized leave, those wee baby leaves are using nutrients but not really contributing anything in the grand scheme of things.
Pests
As I mentioned before, most of these points can be applied to most tropical house plants but there are some things that are Monstera-specific, and one of them is thrips.
Now, don’t get me wrong, ANY plant can suffer from a thrips infestation, but Monstera are especially attractive to them for some reason.
Thrips damage can manifest in a number of different ways (you get the whole roster of symptoms - brown leaves, yellow leaves, droopy) but the actual marks the thrips leave are quite distinct.
Firstly, there are the marks from where the thrips have been sucking – it looks like someone’s taken an eraser to the leave and tried to rub the green off, like this:
And then on the underside, you’ll probably be able to see a load of thrips poop. Yay!
Those little yellow dots? Thrips larvae. Those brown smears? Thrips poop*.
*I assume from the adults. If the babies are producing poop twice the size of their own body I must offer them begrudging applause.
Seasonal changes
Monstera deliciosa don’t like seasons.
Seasons close to the equator are more about changes in rainfall, and winter isn’t really a thing at all.
Monstera may drop leaves, but they could also turn yellow first. Make sure you check for thrips though, because they LOVE a cold-stressed Monstera.
Fertilizer issues
I put this in because fertiliser can cause issues BUT unless you’re fertilising your Monstera every time you water, you’re using a very high dosage and/or your Monstera is very unhappy, I’d be surprised if fertiliser was an issue.
I don’t feed my Monstera when it’s having issues like yellow leaves. For one thing, it won’t help – you can’t cure illness with supplements, but the main reason is that you can rule out fertilsier being an issue.
Light issues
Keeping your Monstera in too bright light can result in bleaching. This is unlikely, but it can happen in very hot, dry environments, especially if you keep your Monstera outside.
More likely is yellowing leaves due to low light. Low light can cause plants to get stressed and look pale and sickly. It can also increase the chances of root rot.
Humidity issues
As I mentioned before, Monstera deliciosa aren’t too fussy about humidity, BUT extremely dry air can cause brown spots on the leaves, and then the leaf will eventually yellow and die.
It would have to be really low humidity though, and if your ambient humidity is 40% or above you should be totally fine.
Other Monsteras are a bit pickier about their humidity. Monstera obliqua need humidity levels of 80%+ otherwise they’ll shrivel up and die.
Adansoniis sit firmly in the middle, and like a medium 60% humidity, though they will tolerate lower.
Shock
The reason Monstera leaves go yellow when they are shocked is that the plant is re-evaluating its resources so it can better deal with what happened.
If your Monstera decides it can better cope with the move from the kitchen to the living room if it only has eight leaves rather than ten, it’ll kick two leaves to the curb without hesitating.
No one ever in the world has said that houseplants aren’t dramatic.
It’s pretty easy to shock house plants – even the most innocuous move of two feet from one side of the window to the other can shock them.
Temperature
Don’t put your Monstera outside in winter. First, the leaves will go yellow, then they’ll go brown, and then they’ll drop off. In quick succession.
Don’t put your Monstera outside in summer without properly acclimating it. If it’s a bit late for that, I have an article on rehabbing sunburnt Monsteras. Just because every leaf has crumbled to dust doesn’t mean that the roots are dead!
Transplant
Plants don't like moving. Whether it's from pot to pot, room to room, or the garden centre to your house. It's not something they're equipped to deal with.
All you can do is avoid moving your plants as much as possible, and if it’s inevitable give them a little extra TLC once they’re situated again.
Water stress
Too much water or not enough.
In both cases leaves go yellow before going brown, but underwatered plants go downhill all in one - they're fine for months, and then the next day they're shriveled and brown. They turn yellow for, like, a couple of hours.
Overwatered plants have a slow and steady descent into death, and tend to go from yellow to mushy.
And this concludes our discussion on yellow leaves and Monstera. If you have any insights or comments, I’d love to read them.
Before you go, you might like these articles:
- The ultimate guide to Monstera deliciosa
- How to care for Monstera deliciosa
- 20 common Monstera deliciosa problems
