This is maralroot.
From the Richter’s herb specialty catalogue (www.richters.com) my herb-interested husband read that this Siberian perennial was easy to grow and has ‘remarkable metabolic and tonic effects … a potent adaptogen that ‘helps help athletes increase indurance, reflexes and concentration, and helps them to recover faster from exertion. Studies show that the root extract greatly increases the work capacity of muscles and normalizes blood sugar levels quickly after exertion, and improves memory and learning. Contains ecdysteroids which have anabolic-like growth promoting effects without the side effects associated with drugs. Violet flowers appear in the second year, reaching 80-160cm/30-60in in height. Grows in deep, well-drained fertile soil in full sun. Very hardy. Seeds are said to respond to outdoor exposure in seed flats over winter, but we find that seeds germinate in flats without cold.’
From Henriette’s Herb Page (http://www.henriettesherbal.com/blog/maral-root.html): ‘Very pretty plant, it is. And people who walk by ask "what's that"? Because it's only in flower for about a week, after which the show is over, and it's rarely grown outside specialty gardens (like a largish herb garden) so people really haven't ever seen it before. Digging the root is major work, and as if that wasn't enough, cleaning it is even more work. No wonder the Russians dig 2nd year root instead of the far larger root clumps of 4-5 year old plants. Don't grow maral root in clay, you'll never get the wire-like tangled roots up. I know, because a friend working on a local herb farm tried just that, a decade or two ago. They made no progress at all with a spade, and about as much with a tractor pulling the plants up. It simply won't work.
We didn’t know which part of the garden this plant would like when we started them from seed in 2009, so we put out 10 in various locales around the gardens. They came through our freeze/thaw winter and are all growing well, the ones in direct sun and best soil are ‘flowering’, if it can be called that. The blossom-seed-head, which looks like a dried thistle even while in bloom (where was the violet-like flower?), looks ominously like something that will carry a lot of seeds. Maybe the finches will like them? Will we have extra healthy finches?