I bought this croton 10-15 years ago, I'm not sure about the variety but I'm guessing... Mammy:

It's always had this tree-like appearance, it's never been thick and bushy like ones I see on Google.

I put it outside when the temps are over 50, then bring it in when it's colder. I have it in a South facing window, and water and mist it weekly.

When it's outside over the summer, it does well and I rarely even touch it! During periods of drought I water everything by hand, of course, so it gets watered then; otherwise, it just gets rain.

When I bring it in, though, it always loses leaves immediately. Right now I pick up 2-4 each day. And you can see in the picture that there are 2 leaves that are brown and about to drop.

What do you think? Too much water? Too little? This is the sunniest window I have, although I COULD put it in a heated greenhouse that gets 4-5 hours of sun if that would be better.