How to grow common mullein

When to plant common mullein

Common mullein is a biennial: it forms a large, woolly, silvery-green rosette the first year and sends up a tall yellow-flowered spike (often 6 to 10 feet) the second, then dies after setting seed. NCSU notes it self-seeds (though not especially aggressively) and thrives in poor, dry, well-drained soil in full sun. It is listed as a noxious weed in CO and HI.

Common Mullein is timed by season rather than your frost dates, so the planting calendar does not generate ZIP-specific dates for it. Check the cited sources below to fine-tune for your area.