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')

Thank you so much, Jay! Your plant looks great!!! I live in NJ where it’s very humid most days, should I try and bring it outside?

It looks like your soil is still too retentive. The browning and slight yellowing indicates overwatered to me, but that could also just mean it retained too much wetness for too long, even if you didn’t water often. Also, are you watering thoroughly so that it drains profusely from the drainage hole? I hate lugging mine outdoors so I admit I don’t do it for every watering, but every third or so watering, I do take it out and water it multiple times until it gushes and gushes so as to flush the soil. The other times, I water it until it flows out the drainage hole and as soon as I see it doing so, I stop, so I can carry a manageable amount of water to toss in the sink.

I find that these love being watered but don’t like any soil that doesn’t drain to “damp” almost immediately. Your soil looks very rich - perhaps you can cut it with about 30% screened perlite to increase aeration so that it drains and dries faster. I used a soilless medium that is mostly coir-based for my soil, but it drains super-fast to damp, and then slowly dries from there. It’s also ridiculously low in humidity here in NV. I find I water at least once a week during our hot summers. It also helps that it’s very under-potted as the roots easily use up the water that this amount of soil holds in these temps. Mine is in serious need of a bigger pot but I’m procrastinating.

The damaged leaves look like they happened as they unfurled. Is it very arid where you are? Or could someone/something be touching them?

Hi Grace!! Thanks for your response.

The soil was previously in very rich soil, but right now I have it in 50% moisture control and 50% cactus and palm soil and the soil dries much quicker! I am thinking the damage done to those smaller leaves was when I had it in the other soil.

I live in NJ, so the humidity here is terrible! I only water it every week and a half when the soil is drier, as I hear these plants like to dry out a little before being watered again.

since repotting it, I have not watered till it drained because I have feared overwatering in the humidity of NJ. Maybe I should let it drain through for the next watering?

Victoria, by "moisture control," are you referring to Miracle Gro? If so, you took a cactus/palm soil and made it wetter, not drier. And if you're referring to MG Palm/Cactus, I used it once years ago and found it to be terrible (though slightly less so than Moisture Control). Not only do they not dry quickly or properly, but as you have found -- they either reliably come with fungus gnats or attract every single one in a 10-mile radius. When it dries, the top dries out and the bottom is still mud. Over time, it becomes complete muck.

But I do have a serious bias against MG in general, so take that for what it's worth to you. :)

I'd recommend a better soilless medium like ProMix HP -- cut with about 15-20% screened perlite. I have mine in a coir-based medium that I'm taking for a test run this year called Vermipro, but that's hard to find. It does drain like a dream, but almost runs dry too quickly. For smaller terra cotta pots with a growing plants, I often find that it's dry to the bottom in one day in NV, so I can't even use it outside, but indoors, it's been quite nice. If that plant were mine and I was going to use that pot, I'd repot it into better soil immediately, OR -- I'd screen perlite to remove all dust and bits, then use it as about 30% of my mix in a significantly smaller terra cotta pot (so as to limit the amount of soil, which limits the amount of water) with the Cactus/Palm MG soil, with none of the moisture control. And then I'd fully flush the soil.

But that's just me!

Do you think it would be okay to repot once again??? Thanks so much Grace for all your help!!!!

Hi Victoria,

While not beneficial to repot often, I’d much rather repot again and again rather than keep a plant in subpar soil, especially if it’s already showing stress. That’s my opinion anyway. :) You have the added benefit that this forum (gardenweb/Houzz now) has some of the most advanced soil information available on the internet, in my opinion. Al and many, many others have shared a wealth of knowledge here—much of which I’d have never tried had it not been tested by so many here. There are some great soil threads in “container gardening.” I’ve used the soils religiously, even though nowadays, I tend to mix and match what I have available to recreate similar concepts. :)

Monsteras certainly don't mind being repotted. Plus, you've already disturbed it once already when you repotted it the first time. It hasn't had sufficient time to establish itself just yet, so disturbing already disturbed roots won't make much of a difference. These plants are monsters, which is how they got their name. They couldn't care less about being repotted.

As for putting them outside, they love the humidity. Mine goes outside every year and it grows like a weed. Not only that, but the leaves get huge. Plus, the only care it gets from me is a blast from the garden hose in the evenings. Which it soaks up and wants more of the very next day.

Not only that, but the roots have gone crazy. They've filled in the whole entire pot, and now the aerial roots are growing out all over the place and along the ground.

As for the soil, a mix designed for cacti and succulents is fine to use, but Monsteras are epiphytic in nature. So I mix in 50% Miracle Gro orchid bark with mine.

This picture, I took last year to show how I occasionally give it a good soak during the hot summer months. Being outside, this plant soaks up water like a sponge. Yesterday, I was tending to it and noticed that I had to resecure the newer growth to the metal stake because it has grown so much this year already. I'd post updated photos, but I haven't had a chance to take them.

Can these plants grow indoors just fine? Of course. But if you can place them outdoors where they're shaded from any direct midday afternoon sun, and not allowed to dry out, then your Monstera will thank you for it by growing into a beast that gives these plants their well earned reputation.