They can be planted directly as tubers or started earlier indoors in pots, but dahlias should be transplanted for outdoor living before they are a foot tall.
You may be able to get earlier blooms by jump-starting your dahlias indoors
Learn the basics of good dahlia care and these flowers will reward you for many years--possibly for generations!
Learn when and how to pinch, disbud, and deadhead your dahlias. This will increase the quality and quantity of your blooms.