Answer: Your zip code places you in a nominal zone 6B, but Musa basjoo is considered root hardy to zone 5 so it should be hardy for you, yes. It would need to be very heavily mulched in late fall to protect the roots, however, as wrapping the gtrunk would not be sufficient. You may also find that age of the plant, wind exposure and microclimate really affect what happens each winter beyond the actual low temperatures reached. New plants generally would be expected to die back to the ground each winter, a more established plant might possibly retain some above ground growth if well wrapped and insulated and the microclimate is favorable and the weather cooperates. You might want to consult with your local county extension and/or professionally trained nursery staff to see if they can help you analyze the growing conditions where you have tried your Musa basjoo and see if they have more specific suggestions based on a more detailed understanding of how you are growing it. I'm sorry you have had trouble with it.
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