Anyone grow the collarette dahlias?
Collarette dahlias are type of dahlia flower. They typically grow 3-5 feet tall. Bedding mix dahlias grown from seeds are variable in flower type but consistently grow less than two feet tall. The best bedding type dahlias are grown from tubers or cuttings. Two sources are Swan Island Dahlias and Corralitos Dahlias both of whom have web sites.

I grew these from seed and was quite pleased with them. They made lovely flowers - some of them quite prolific. They are a bit bushy and stay under 30 inches. Mostly various shades of magenta/red/orange with collars in white and sometimes yellow.

Will these make tubers that can be lifted and stored for the next year?

They do make tubers, but I have found them to be difficult to overwinter as the tubers tend to be stringy and small. I don't bother digging them anymore if I do end up impulse-buying them in spring.

But by all means, try! They might do great for you. Maybe others have had better luck.