For most exotic gardeners in Canada, there are a few significant limitations when winterzing banana plants outdoors. The first, is that Musa Basjoo is likely the only variety that you will be able to successfully winterize assuming you are not using any heat source. The other main limitation is that your banana plant will die back to the ground each winter. This restricts how high your banana tree will ever grow. If you want your banana to grow 12+ feet tall, you need to save last seasons trunk. To do this, follow our 5 step process:
1. Before the first frost, cut all of the leaves off your banana plants. Leave only the top leaf.
2. Carefully dig up your banana from ground.
3. Remove most of the dirt and roots from the base of the banana. Don't worry, your banana will grow new roots next season.
4. Allow your banana trunk to dry out in sun for 2-3 days.
5. Store your banana trunk in a cool area between 1-10C. Garages and root cellars that stay above freezing are ideal for this.
6. Plant your banana trunk in the spring after the last frost. Begin watering and your banana will begin growing from the top of the trunk.
That's it! Now you can grow tall bananas in your yard. This work for other banana varieties also including Ensete ventricosum.