I forget, is it lemon balm or lemon verbena that tastes best? They're similar, right?
I found seeds for lemon balm...but haven't seen verbena here.
Well...lemon balm tastes good. Just got my first lemon verbena a few weeks ago and haven't really evaluated it yet.
Lemon balm loses it's flavor when picked. Lemon verbena will have fragrance and flavor when it's an old dried dead thing! I am thinkin' in your climate the Lemon Verbena also may be a bit more challenging. You need to look for a live plant to transplant. You can order them from a place in Canada so I know it is possible to grow it in Vermont though!
Lemon balm is good to grow from seeds though I think. Although, the lemon balm I got from OT has been the only one to overwinter and act like it's supposed to. When I've planted from seed it's never made it through the winter.