Self-sowing, but I wouldn't be without it as it mixes wonderfully for some serendipitous combinations. Tall, violet, kitten-tail spikes are perfect with Heleniums, for instance. Blooming all summer, the semi-evergreen foliage is aromatic and bushy, and deer-resistant; 18" tall.
Minimum temperature: -10° F
First photo by Salicyna - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=53805365
Second photo by Salicyna - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=58465208
