Most of my plants are from Home Depot, but remember not all plants are safe for your chameleon.
For the ones that are chameleon friendly, I make sure to thoroughly rinse all the leaves as well as remove the plant from the soil and rinse the roots as to be sure there are no harmful fertilizers left on the plant. I then re-plant it in a soil without fertilizers and then hang it in the cage.
I hope this helps!