I don’t think it’s a perennial. More like biennial.... but I pull out the really big plants that are going to seed except for a few to allow to go to seed, and any old and decrepit ones that aren’t doing anybody any good, so I can’t say if I’ve allowed any to stay in the ground more than a couple of years to know for sure that they are NOT perennial.... I’d always assumed the ones that survived the winter and growing are in their 2nd year.
Yours don’t self-seed?
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