Thanks for the reply. I might have been over cautious with watering so will up the water and increase the light. Hopefully that will sort it.

I should have added that the discolouration of the leaves start near the middle of the leaf then travel outward which I found a little odd as I expected it to start at the edges.

Fingers crossed. Many Thanks.

From what I can see of the soil in your pic, the roots are likely rotting. There are some good, recent discussions on the Aroid forum about Monstera, which include info about the kind of well-drained/airy soil they prefer.

Misting may do more harm than good. You may feel differently about doing it after reading about it here if interested, under foliar diseases.

Hi purpleinopp. Thank you for the links, lots of info to digest there. Not convinced I'm overwatering (I had just watered in initial pic) and its a premium potting mix. I guess the only way to be sure is look at the roots.

At the moment I'm thinking maybe the misting is causing the problem.

Not sure if I should remove the affected leaves as there are brown spots on 3 out of 6 leaves. (top and bottom still clear).

I've attached a new photo to show more clearly how it starts as a small spot in the middle of the leaf.

Thanks for your help :-)

Overwatering is really a misnomer. What's really going on is that some types of soil can stay moist for too long, because of the texture of the particles, and they way they lodge tightly together, filling all spaces in the pot. When that happens, there are no tiny air pockets and roots can rot. When a drip saucer is used, the bit of standing water in there can also be lethal to roots. When roots are rotting, they are unable to deliver moisture and nutrients to the leaves, and the effects manifest as yellowing, brown edges, eventual death of the plant.

Learning how to avoid that can greatly increase your success with any potted plants. To read specifically about that, this article is extremely informative.

Bagged potting soil is often not what one would describe as well-drained, especially after significant time has passed. It can settle (in conjunction with some decomposition as well) and suffocate roots as it turns into muddy muck. Meanwhile, the roots have filled the spaces they find suitable, and eventually run out of room to grow.

A well-drained soil... water flows out as fast as you can pour it on, and dries within a few days. The way (stuff to use, amounts of it) to achieve that is the worthy subject of debate, but about the principle, there is a huge confluence of agreement. Ideally, about any (non-cactus) plant would like to have soil that is never dry, never soggy, always well aerated.

Thanks for the info, its a lot to take in but very useful.

The reason why I'm so unsure about the overwatering theory is due to several factors. Our house is very warm 22-24 deg C and dry (due to a wood heater). When I water, the soil is always dry for at least the first inch. Water will seep from the pot quite quickly so I'm not thinking the soil is too compact. The plant is never allowed to sit in leachate.

Also I was under the impression that over watering caused yellowing along the vein and leaves rather than dry browning. The discolouration on the leaves start as a brown dry dot with a yellow halo then gradually expand. These spots start any where on the leaf middle or edge. I cant seem to see a pattern. Also no wilting.

I orginally suspected a fungal or bacterial infection (never seen either in my houseplants before so clutching at straws). Now I'm very confused.

I'm going to check the roots and soil for sign of damage. If thats all clear I'm back to clutching at those straws!!

Thanks for all your help, much appreciated.

Have you had a chance to look at the article about the dangers of misting? I think you'll stop seeing the spots spread so fast, possibly at all, if you stop misting. If you scroll down in the article, there's a table about symptoms and causes. Don't forget Jean's advice about light, too, I agree.

I bought Monstera in nursery and then I noticed some small yellow spots underneath the leave, I used some soup cleaning the last one. Now I noticed that all my leaves have these spots. What could it be? Is it possible to save my plant? Thank you

Hi, interested in wether you ever got to the bottom of the leaves browning from the centre of the leaf? As my new cutting has just started doing this !

Best regards natalie

Same thing is happening to my monstera, help! Browning leaves, one by one.

I had a big problem with this and after trying various things, I was underwatering and due to my issues, I think it was bacterial blight. Pothos and philodendrons are very prone to these. I removed the really bad leaves, sterilizing the shears each cut and am watering more. I sprayed with organic fungicide. My plant has perked up and I haven't seen much spreading further of the browning. I feel like a lot of this is research, trial and error. I hope you all are able to help you babies <3

Hey guys! I have a baby monstera, all the bottom leaves turn yellow/brown one by one. Are these signs of moisture imbalance, as I only water weekly sometimes less when the soil is still hydrated? I have bee cutting them off, should I be doing this? Appreciate any feedback, TIA