I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
I suggest you do an air layer on the top part. The following web site shows how to do this.
Then take the remaining stalk back to a desirable height and it should respout after a few weeks and begin to grow a side shoot or two.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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