Cover deeply with mulch or dig and store. Do one or the other immediately.

If you really are in USDA 7 I suppose it might have gotten cold enough to zap and perhaps kill the rootstock already. Have you had hard, penetrating frosts? Here, where like many people posting on the forum we really are in USDA 8 today is the first day it has gotten cold enough for the rhododendrons to start rolling up.

Even when they manage to survive the winter outside here the cool summers may not bring the top on fast enough for full development or a full season of bloom.

Thanks for the advice! I may have been a little late on that one. As of now its droopy, frozen and covered with snow. I will try another one again next year.

Figure on cannas being annuals. Even when they survive the winter, it takes so long for them to get going again in spring that it's hardly worth waiting for them.

I think people do dig them up in the winter, or keep them in pots and stow them in the garage or sink them in a deep pond where the water doesn't freeze solid.

Sounds like it was in the ground long enough to grow, from a 4" pot to 6ft tall! so it may survive. The tops always die back. You just need the roots to survive.

My friend sticks hers in her garage in their pots and they live every year. I've killed them on the patio wrapped with tarps and xmas lights, in the shed and leaving them out. Only in my heated greenhouse do they live for me but they are so dang big they take up too much room.

If they don't sit in waterlogged soil...or get hit by a major Arctic blast, my cannas survive in the ground most winters. As they multiply, I leave some in the ground & grow a back-up plant in a nursery pot. I sink the pot in the garden in the late Spring. Before we get a hard freeze in the Fall, I dig up the pot & cut the stems to about 6", then store the pot in my garage for the Winter. I give the pot a small drink of water every 5-6 weeks to keep the soil from over drying.

This past season was very poor for gardening in general and the heat lovers, like cannas, didn't attempt to bloom until well into the Fall.

I like species-flowered cannas because of the nectar they produce...much appreciated by hummingbirds. My favorite to date is Peach Gigantum. It's very tropical looking and the blooms are held about 12 feet in the air!

The two I left out of the greenhouse are dead. They are mushy and laying flat on the deck.

Well, we just got home from the Caribbean only to find cold windy weather and what was still green in the garden when we left is now brown and dead or expired for the season. There are such beautiful tropical plants in that part of the world. As I enjoyed viewing the lovely plants I often thought of that poor frozen limp Canna I left back home. Oh well today I chopped that mushy mass to the ground. I will try again next year as it is such a lovely plant.