It won't be long before we get a frost here so I need to start bringing in all these gorgeous begonias. Newt, you said that you keep them wintered successfully in a sunny window. Can you advise me on what kind of pot works best and the kind of soil they prefer ? I've never had my soil analyzed but it is dark almost black in color and is rich in organic matter as I mulch leaves and grass clippings for years. My problem is everything thrives in it. Can I use the garden soil? Thanks a lot, Coralbelle..