I got a begonia with a help sheet saying it was a Begonia x tuberhybrida so when it started to die back in November I assumed dormancy and pulled the plant out, shook the dirt off but I can't find a tuber. There's only one big fuzzy stem above the dirt and lots roots underneath. Could it be a really tiny tuber? It produced large pointed leaves. Did I just kill it or maybe it was already on its death bed!

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