These are some of the seedling Cannas that I've been working on. These are about 4 years old now and although they usually bloom the first year from seed, the blooms don't really come into their own until they they are a few years old. One of the parents was a species Canna that had small flowers and the pollen parents were various sizes and colors. All of the foliage is a blue green with long narrow leaves. If you're used to the Cannas you see most of the time, this would look very different. Unfortunately, I didn't get much of it in the pictures. They also tend to be shorter, most only about 3 feet tall.
Anyway, this first one is a nice baby pink.
And here's a salmon colored one.
This is a darker pink
And a pale yellow with some peach colored spots on some of the petals. One of the parents had some speckling on the petals, but not all of these have picked up the trait.
This last is a red that is pretty much identical to the species that was one of the parents. The plants with these red flowers are much more robust than the ones with the pastel colored blooms.
Hybridizing with Cannas is pretty much like with any other blossoms - move pollen from the anthers of one bloom to the pistil of another. Maybe a post on the whole process later. I sometimes plant the seeds right away, but you can also put them in a zip loc bag and store them in the crisper drawer of the refrigerator until you're ready. I plant them in small pots and size them up when they're a couple of inches tall. They like warmth and so I start them in the greenhouse, but a warm room under grow lights would work just as well. Just keep them damp and they're as easy to grow as marigolds. If you're growing Cannas this summer, just check the bloom scapes after flowering and you may find some seeds to start since the bees do a good job of fertilizing the blooms.