When overwintering potted begonias, should they be trimmed back?
Certified GKH Gardening Expert
If you are allowing the plant to go dormant, it may be a good idea to trim it up and stick it in a dark location. Otherwise, you can allow the plant to continue its growth, treating it as a houseplant. Of course, it may suffer less stress if trimmed as well. This is up to you and dependent on the type of begonia you have. Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/flowers/begonia/wintering-begonias-overwintering-a-begonia-in-cold-climates.htm