Hello and thanks for contacting us at Gardening Know How. Follow this link for some help with your zone. Looks like you are either zone 6 or 7,
In zones 7-10 cannas can be safely left in the ground during the winter. Zone 6 is a median climate for cannas. Cannas grown in zone 6 can be left in the ground during less severe winter seasons but always have the possibility of freezing during more severe winters. Cannas grown in zones 5 and colder must be dug and stored during the winter. So looking at your zone I would say it is best not to plant them them out now and leave them all winter as you could lose them.