Beginner Gardening: Please help my sad purple Calathea..., 0 by Plants4myPots

Plants4myPots wrote:
I bought this plant last November, when it was happy and probably three times the size it is now. I had displayed it in a very low light indoor location for a couple weeks, and it declined. Since about January, this plant has been outside (zone 9B) in a fairly shaded location that gets some nice morning sun and it has continued to "survive". Meaning, it puts out new leaves, but the plant doesn't seem to get any taller or fuller. The leaves just come up, but stay near the "core" of the plant near the base of the plant, and then slowly decline.

I sprinkled some granulated fertilizer on it a few weeks ago, and that stuff has perked up every other plant I've ever put it on, but this poor thing continues to look pitiful.

All of my other plants are looking absolutely fabulous, and I'd really like to get this one going again. I'm doing a bunch of puttering around the garden today, so I'm really looking forward to your suggestions.

Thanks!