Growing Cannas from seed

I've checked all my books, including the Exotics one, and nowhere does it suggest growing them from plant produced seed. Most of them are hybrids, and as you've already done, are propagated by rhizome division. Might be fun to see what happens if you give it a try, but I can find no info as to how to treat the seeds in order to grow them.

I brought some back from Australia a couple of years ago, planted them as normal - no soaking, chipping, what have you. Some germinated quickly, some took longer but most of them germinated eventually. Being from Australia I don't know what type they were, just that the flowers were red. I got them through one winter ok but last winter saw them all off. Good fun though.

Having gardened in the tropics, these seeds germinate readily. I presume the simple answer is heat.
Interestingly, the species Canna, rather than the flambouyant hybrids of meaningless nomenclature, was extremely difficult from seed, even though the diminutive red flower screamed to be propagated just because of it's beautiful delicacy.
There again, the hybrids were always more successful at altitude, so cold night temperatures seemed to suit them well.
Make of that what you will, because I certainly never could!