Quart pot seedling tree peonies shouldn't be that expensive, I'd think less than $40. I've purchased larger seedlings before that had already bloomed so were a known commodity, those were around $100 from The Tree Peony Garden when she was open. As far as Rockii being more expensive I don't see why, they are more hardy to cold but you wouldn't care about that! Unless they've bloomed and proven to be unique I'd think they'd be around the same price. Maybe if the parents were proven to have nice seedlings?
Alex, the first tree peony seeds I planted were from the APS seed program. I planted them outside in a shady spot and just left them alone, I had seedlings germinate and emerge over the next 4 years. Crazy, huh? The few that survived our CO weather are in AL now, hopefully I'll see them in a few weeks.
