What makes you think you may have "overdone the pot size"? Is the soil staying too wet? How does the plant itself look?

Hi there! So yes, the soil was staying very wet. But also, the leaves have brown edges that are curling and the dark green is becoming a yellowish green on new leaves. Some of the mature leaves have also changed to yellow. it isn't praying properly, but it remains perky in structure and isn't wilting really. All the leaves are just... dying, it seems.

If I removed all damaged leaves, there would probably only be about 5 or so remaining. I planted it in a terra cotta pot with Miracle Gro African Violet soil, so the pot is breathable but the soil mixture is known to retain water.

I spray its leaves quite often, group it with other plants, sit it on a grate with a plate of stones underneath, nothing is working. It's near a south facing window that is covered by large trees but still allows in sunlight.

P.S. I should note that since my first post, I reported into a smaller pot, which is the terra cotta pot I spoke of in the post right above this. Everything went down hill when I decided to repot in the first place... it was purchased in a plastic pot.

Did you check the roots while you were repotting?

Yes! I actually just checked the roots again, and they are healthy. I also added a little bit of dry soil because, even in terra cotta, it is refusing to drain as adequately as I would like it to.

So, a small update... I pulled back a curl of one of the leaves, and it has some white webbing in it as well as a few bugs... but, nothing indicates an infestation and none of my other plants have spider mites. I have the Calathea grouped with a nerve plant, a ruby ficus, a mauve anthurium, and a Beefsteak begonia. Other than my miniature orchid, those are my tropical/sub-tropical plants I group together for a greenhouse effect. All my other plants are succulents, and I have never killed nor struggled with a succulent... just the house plants!

The symptoms you describe could apply to overwatering but might also be fertiliser burn. I don't know Miracle Grow soils but there are often negative comments about them on gardening sites, particularly about being too water retentive. But it might also have too much fertiliser included in it. With the "white webbing", might that be fluffy Mealy Bugs?

Well, I contacted the gardening store where I purchased the plant, and they use miracle gro on all of their plants. Everything I buy there is super healthy! The Calathea I purchased was very healthy when I brought it home. So, I'm not sure.

If you want to recommend a good soil, I would appreciate it!

My Calatheas are in the garden, so my medium is garden soil. We don't have "Miracle Grow" products here so that's why I said I don't know about it but there's often comments on this site and others about it being too water retentive. There's only the 2 things already mentioned I can think of that might produce the symptoms you mention in your plant. Pearlite added to the soil would improve drainage and flushing the soil a number of times would remove any excess mineral salts.

Thank you for the tips. I took a look at where the new leaves were attached to a stem but had yet to grow, and it looks like they died before unfurling. I guess I need to let it dry out for a bit and see what happens.

This conversation is over a year old...if "skatelynmat" is still checking in here, let me know. I have some tips for Calathea.