Ideally Bananas,   that are not grown in containers, should be planted in the sunniest warmest place in the garden usually the south or southeast side of the house, with some protection from Wind and severe weather.  Plants left in the ground should be well mulched, soil may be banked around the sites of the trunk just before onset of a cold spell. Covering the top or wrapping the trunk in Insulation and covering with plastic to prevent freezing is practiced in the Pacific Northwest. Care should be taken to prevent infestation of rodents. In colder areas Heating cables may be added to the wrapped Banana Tree to prevent freezing. 

A high Nitrogen Fertilizer     should be applied at the start of the growing season, additional application of fertilizer may be applied at bi weekly intervals. Or a high nitrogen slow release fertilizer can be used instead at the beginning of the growing season. In hot dryer areas or in a Greenhouse or Sunroom, Bananas may be susceptible to spidermites, on smaller plants washing the leaves will correct the problem or alternatively spraying with Safer's Insecticidel Soap or a light horticultural oil.