After the first hard frost, cut the pseudostem (trunk) with a large sharp knife, make a clean level cut across at a height of 8" to 12" from the top of the ground. After cutting place a type of wire evenly around to hold mulch up around the pseudostem (trunk).
Banana Musa Basjoo
The Basjoo is perhaps the world’s cold hardiest banana tree. It is hardy planted in ground to -3*F and with protective mulching it can survive temperatures reaching down to -20*F. Its inflorescence is one of the most beautiful of all bananas. It is a great landscape plant, it lends a tropical appearance to any situation.