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.

Monstera do well in soils that hold moisture but also drain well. It's not unusual for a nursery to water their plants several times daily, so don't water it again until it's gone relatively dry. If it seems that the soil takes a long time to dry out, it may need repotting, which you can do later in spring (or just make the mess indoors; I prefer to do it outside). If you do, repot in any good potting soil with some Perlite added. Half might be a bit much, but it does depend on the potting soil. Very heavy soils might need half. Lighter ones, a quarter or less. Some soils might be fine as-is. For Monstera, don't pot in a large bark particle soil. They don't like soils that light and airy, and prefer soils that retain more water than that. Bark fines are not an issue. New plants seem to always arrive with shipping and transportation stress, so I wouldn't think too much of a few brown spots off the bat. For right now, give it proper light and care, and see where it goes from there. You can expect some marks to show up over the first week or two just from being brought home, too.

Yours is slightly larger than mine. Mine is my first and I got it at a nursery in early June. I really like it. To me, the marks on your leaves look like shipping damage from the leaves being bent too much. The younger leaves yellowing could be just from acclimation to your new environment. The leaves pulling out and the new leaves that appear to fall apart - I am not sure what that could be. It probably all began with the lack of drainage you mentioned. Fungus gnats love moist unventilated indoor soil. I used to have a lot inside in the winter and none now in the summer. Others on this board can give you some more help than me. I've had a few indoor plants that began dying in early Spring. Then when I placed them outdoors and in the ground they ALL perked up. My banana had several treatments of copper fungicide even after being planted in the ground. It's beginning to look nice. Back to my M. Deliciosa - I place it outdoors almost daily in dappled sun and never in the wind. It's doing well. No issues. I bring it in when windy or if rain is eminent. I also back off the water. I only water when I can detect dryness by sticking my finger 1" into the soil. It's hard for me to not water like I do other plants. But I know they have aerial roots in their natural habitat and climb up trees. So their roots are exposed to the air. Here's mine when I got it on June 10: https://st.hzcdn.com/simgs/48e2ed860b1dde23_9-4068/home-design.jpg And here it is outside tonight - 3 new leaves have opened since buying it. It still bothers me to see the soil that dry. Those flipped over chairs around them filter the sun they get: (on left is Philo. 'Brasil, center is Pothos Epipremnum aureum 'Manjula')

Hi, I recently noticed tiny dark spots on my new monstera leaf. This hasn’t happened to any of the leaves that have unfurled in the past. They appeared on this new growth that came from a cutting that I was propagating in water. I took the cutting off of an older plant that I needed to get rid of because of spongy yellow mold in the soil/roots. The other cutting I took from the same plant put out a new leaf as it was in water as well. That one came out totally fine. I was wondering if the spots will go away as the leaf matures or if I have to worry about some other kind of mold or bacteria. Thank you!!