hasty22

Hello I also live in Canada. I live in Vernon BC . I have grown Musa Basjoo for several years. When I transplant pups I dig a hole add rocks/gravel for drainage. I then use native soil with a mixture of sunshine #4. I would never use manure/compost. Water as necessary, but not to much in colder weather. Once banana show signs of growth and temperature warms up use a water soluable fertilizer like miracle grow all purpose. do not use a slow release in summer. Unfortunately I think you have root rot, possibly from manure or overwatering. If you plant is still turning brown/black I would recommend pulling it out of ground and taking a look at roots. cut off anything rotten. replant in ground with a soil with proper drainage.