I have done that this winter as well for about 30 of them. They are about 2 months old and about a foot. This will definetely give them a good start on the season. I put mine in a long plastic storage box about a foot deep and cover, and put under grow lights. It's also a good way to see which corms are viable and not waste valuable growing time in the summer.

I was thinking about starting mine too but I don't want 4 feet tall canna in my house in the beginning of May before I can plant them outside!
asageman- you said yours got to 12" after 2 months indoors?
if that's the case maybe I could start them now. I don't have grow lights though I wonder if a west window would be sufficient?

I only have four but three of them have put out growth already. A good start.

Hi Rita,

I just bought a few canna also, Lucifer, Wyoming, Picasso, and Durban. What size pot did you plant them in? I have large pots that I want them to grow in, would it be ok to plant them in there first or should it be a smaller pot? One more question do you put them outside during the day with temps in the 70's? Newbie canna grower here so any advice you can give me would be most welcome.

TIA,
Ten Steps

I started mine in small pots, just big enough for the tuber to fit. Its not as if I am going to keep them in the pots. They are going in ground as soon as the get some growth and the weather is warm enough.

I do bring them outside. In fact I left them out all night for the past few nights as it was relatively warm. But its too early to plant out, we could still get hard freeezes. So the pots are a safe bet as they can come in if necessary.

This is the first time I have tried them early in pots. Mostly, I just wait until it is warmer and them plant directly in ground.

@asageman You are wasting electricity putting them under lights if there are no leaves. Wait until they have some growth above ground or not. It's your $$.

I need to clarify. I pot them up inside and put some of them under grow lights after they have leaves. The corms will come up with leaves even without any lights.I have some seed grown cannas that are 2+ feet under grow lights 12 hours a day but they still have a tendency to get brown leaves.

I always pot my cannas indoors end of March. The sprouting takes forever, and here in Ohio I don't have the time to put them in the gound in May, and wait until June for sprouts. Last year I put them directly in the ground and the tall ones didn't even flower. I think soil temperature has more to do with it than anything, so here's how I've been doing it for 4 years now:

In February I bring the rhizomes up from the basement (about 45-55 degrees down there) and set them upstairs. In Feb my furnace is blasting at 62-70 degrees, so the warm air tells the cannas to wake up. I store them in plastic grocery bags- nothing fancy.

By March you can see the eyes start to swell and turn into horns. I lay all the rhizomes out by variety and sort them by size and health. Then I take some miracle grow potting soil and put about 4" in the bottom of 12" black plastic pots, layer the rhizomes on top, and cover with as much potting soil will fit. I've read you're supposed to put the bulbs 12" apart, but I crowd them really close together because my growing season is so short, I'm just going to dig them up and divide them in a few months. I think they look better/more natural crowded anyway!

Ok so after you pot them up, really soak 'em and let them drain. I put the pots back in my kitchen on the linoleum floor and let them bask in the heat of my house. DON'T WATER THEM! You don't want them to rot, you just want to "inspire" them with that initial soaking. Once they sprout, sitck your finger in the potting mix to see if it is too dry and water as needed... not too much while indoors!

Now they should have leafed up, maybe around a foot or two. I start hardening them off by putting them outside, but bring them in at night. I put mine in the ground this Saturday May 15th when they were about 3 feet tall (tall variety) and 2 feet tall (4' variety)

Another advantage of putting them in the ground when they are so tall, is that they are taller than the other plants in the garden so they get more sun earlier. If I put the rhizomes directly in the ground, all my hardy perennials would be shading the soil and keeping the dirt cool- a no no for tropicals.

I have photos of this whole process I will try to get them up