Canna Cannova are not hardy and need protecting in the winter. This makes them ideal for pots which can then easily be moved into a green house or conservatory for frost protection and to keep the winter wet off plants.  Canna are fast growing so need a really big pot with plenty of room to grow.  They will also need regular watering and feeding to enable them to grow and repeat flower all summer.  Make sure to remove flowers once they are dying back or the plant will not keep producing new flowers.  In town and city centres, plants may survive the winter if a layer of mulch is applied.  In other areas move plants into a frost protected area.