Calla bulbs are rounded in shape, light in color. Canna rhizomes are longer, sort of like fat fingers with swollen areas (eyes) on them. They are dark in color. If they were not potted when you bought them that info should help out. Have any of the leaves come out yet or are they in the rolled up stage yet? Canna leaves will be larger than callas. Try googleing Canna lilies and or Calla lilies.

I tried looking it up actually. I believe the bulbs were more round than long but can't be certain...First time doing it...The leaves are light green but are still in the rolled up stage. I guess I will have to wait and see. I actually don't even know what colour they will be. This should be interesting. Thanks for the response.

Here is a picture of the leaves now that they are coming. Does anyone know if these are calla or canna? I think they are canna. Do Canna all get really big? A little worried that I planted them in the wrong spot.

Here is a link that might be useful:

Yup, them there are canna lilies.

Man!!! Oh well. Do you think that I will need to move them from the spot I have them. Perhaps in a pot? I wonder if they will take up a lot of room or if I should wait and see what they do. I have three so very close together in the garden and there is a japanese barberry, a delphinium and lillies right close to them. Not to mention a few cosmos and coleus. I don't want to disrupt the canna's growing, but maybe potting them is a safer spot??? Does anyone have pictures of theirs in the garden so I can get an idea of what they will turn out to be. I have worked so hard on creating this garden and don't want, amongst my burgundy and chartreuse foliage and pink and yellow flowers, to have these three towering plants with red flowers (if that is the colour they typically are). Hmmm...I sound like it is going to take over the garden...ha ha ha...are they?

Well...Canna's can get quite large and as they grow multiple stalks will emerge. Most of them get to about 5 feet in height in my zone 4 garden.You might want to consider moving at least a couple of them into pots. Good luck.

Can I only put one canna bulb in a 20" pot? What is the smallest size of pot they require?

That is about the smallest pot. You could put a couple in one.
Cannas grow big!

BTW, neither Callas nor Cannas are really lilies. :)

Well, I took all of your advice. I moved the canna into a large area and actually bought four more!!! Ha ha ha! I put on in a 20" pot and it is getting really big. So I am very happy now. I hope I like them...never really cared for them in pictures but I love the idea of the tropical look. I am doing Elephant Ears this year too so maybe all will be well. Thanks!