...that is the question.
'Dahlia blooms are showy, but it’s their edible tubers that make them an excellent addition to kitchen gardens.' ROB CARDILLO
To those of you who have asked what colorful and somewhat showy flower I got in my hand on my Facebook avatar it's a Dahlia. Dahlia 'Thomas Edison'. I know that the native americans (Aztec) used the dahlia tubers for food, but I have not tried them ... yet. I can would image that the structure would be similar to the structure of water chestnut and I've read that they taste is very different depending on how and where they grow.
Learn more about edible dahlias and how to make a Dahlia Salad, recipe in this article. Mother Earth News