Move to Colorado Springs from Jax, Fl and dug up some of my grandmother's cast iron plants from my shaded yard. I wasn't able to bring very much of the plants' original dirt with it so I bought a huge planter, filled the bottom of the planter with mulch (I did this to cut down on the weight and to make drainage better) put fertilized potting soil and then the plant. My plant is dying and I don't know why. I love this plant. It's a part of my home and a huge part of my grandmother's remembrance to me. I've always been GREAT with plants, indoor and outdoor. Thank you, Jen
Cast Iron Plant Is Turning Yellow and Dying
Certified GKH Gardening Expert
Your plant is likely stressed from moving from outdoors to indoors.
Yellowing leaves can indicate a watering issue, to much or to little.
Also could indicate insects or disease.
I would lean to the dry side for the plant, make sure the pot is well draining.
Also I would treat the plant with Neem Oil.
Neem Oil works as an insecticide and fungicide and is safe for people and pets.
It is a good idea to treat the plant when it come from outdoors.
Here are some links for you.