if you are zone 4 .... they need to be dug for winter.. and stored indoors ... otherwise.. they are annuals in such an area ...

its one of those plants ... that are perennial in native areas.. and annual up north

i grew them for years ... digging.. drying and storing them on the cold basement floor under the stairs for decades .. and then just called BS on all that.. and gave up on them .. lol ...

looks like a city planting.. i bet in mid fall you might track down the department responsible.. and find out if you could have a few ... i highly doubt they will be storing hundreds of rhizomes ... over winter ...

but be careful... collecting them can be addictive.. lol ... next thing you know.. you will be digging a root cellar out in the yard.. to store them all ... along with your glads .. and all the other 'roots' that need winter protection ...

ken

https://duckduckgo.com/?q=canna+rhizomes&t=ffsb&iax=images&ia=images

Thank you gardengal and Ken.

that sounds like too much work for me, but i was so curious as to what they were called.

mystery solved.

Or, if you have a basement, you could put them in a big pot, stick it in your basement after frost knocks the foliage down, then stick it back outside when it's above freezing @ night again.

Or just plant in spring and treat like an annual!! No need to dig up unless you want to. The tuber will freeze and turn to mush if left in the ground.

They're really cheap, so treating it like an annual is cool. I always dug mine up and tossed them in paper bags. Eventually they got really big, like wagon wheels, so I'd cut them apart and store the pieces. When I got bored of them, I just let them in to rot back in during winter.

Years ago there was a putt-putt/par-3 golf course near here. The woman who owned it planted cannas to outline the holes (like hedges) on the putt-putt course. They were gorgeous! and this is in z5, so she used to dig and store them all over winter.

I haven't seen cheap Cannas. They're usually in a 1-gal. or larger pot for $15+. Annuals in that price range do not fit my budget, and I don't consider any plant over $10 as cheap, as a personal interpretation.

If you buy the tubers unpotted they are often quite cheap. The tubers grow readily, No trick to it.

That is true, but I've never seen tubers for sale.

Lots of nurseries have them. Just google "canna bulbs for sale".

Box stores - Home Depot, Lowes, Walmart, etc. - sell the bagged tubers in early spring, together with other summer flowering bulbous plants like dahlias, lilies etc.

That is good to hear, thank you. Some of those stores may have them, but not all.