I have 5 tiny cannas from seed - how large should they be before I set them out?
I have 5 tiny seedlings, too. cutest lil things. I would like to know how long before they will be ready to plant into the garden.
Anytime after your last frost date if good. Make sure you harden them off before throwing them to the elements and you will be in good shape.
Canna are related to Bird of Paradise ( Strelitzia ), Bananas, Gingers and Heliconias. They even look a lot like Strelitzia Reginae ( Orange Bird of Paradise ) and the seeds look very similar, except that the Strelitzia seed have downy feather-like orange tufts on them. Canna, being a highly cultivated plant is likely more durable than Strelitzia which I find to be extremely resiliant to division and transplanting.
I expect therefore that Canna can be taken out and planted right away, given that the temps are favorable. I've divided Strelitzia Rhizomes in Winter and late Spring without problems and even the worst looking piece of Strelitzia rhizome that I would have never expected to produce a plant have successfully regenerated.
I have only recently successfully germinated my own Canna seedlings ( Canna x Generalis ) and plan to transplant them perhaps even this weekend. See pictures in thread I posted call 'Observation on Germination of Canna Seed'.