How can I force dormancy on my Begonias. I am away from home, travelling for a year and unable to pot them up at the usual time. I notice that if left longer than normal, when I come to pot them up, they have already sent shoots upwards. I winter them in a basement of approx 60 degrees, stored in paper bags.
Outside United States
Thanks for your question. When you say begonia 'corms,' I'm assuming you're talking about tubers (as in tuberous begonia.) The only way to 'force' dormancy on tubers (and corms and bulbs) is to place them in close-to-winter conditions. Since you've already dug them up, they need to be placed in a cool space. I'm thinking that 60 degrees isn't cool enough for them to think it's winter. Here's a link to a begonia expert, and his explanation about tuber storage.
I hope this helps. Good luck!