This subject came up recently over on the site talk forum, where I questioned where to post threads on dahlias. In short, are dahlias a perennial, or not?
They are tubers, so I don't really think you can call them a bulb.
They aren't herbaceous perennials (or are they?), and they are not shrubby perennials.
In the colder climates, they aren't perennial at all, in the sense of persisting indefinitely in the garden. Come winter... they are gone. You have to dig them up and store them and replant them in the spring, if you want to keep them. Even here, in my garden in Zone 9b, their longevity is questionable. Most of mine have overwintered in the ground (unless the ground was saturated), but the ones left out in pots don't survive. (Ask me how I know.) Moreover, the short bedding type dahlias ('Figaro' comes to mind) are typically sold as annuals here.
So what say you? Are dahlias perennials or not? And where, on this site, would it be proper to discuss dahlias on their own (apart from such things as their use in a perennial garden)?
Dahlia 'Cafe au Lait'
). I did have one spot in my garden where everything seemed to die, and that included a dahlia which I had there. We finally concluded that (although the top of the ground looked dry) the soil was too wet.
