Common Mullein plant profile
Verbascum thapsus
A biennial flower for full sun.
Last updated .
When to plant
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.
The calendar shows this cited seasonal window as an approximate band. It does not convert the season into frost-adjusted dates.
Open Common Mullein in my garden calendarShows the source-backed planting season, not frost-adjusted dates.
Growing conditions
- Sun
- Full sun
- Lifecycle
- Biennial
- Hardiness
- Zones 3a to 9bFind my hardiness zone
Common problems
Watch for these
Also watch for: self seeding, weedy, snails, needs staking in rich soil.
Evidence trail
Evidence behind this profile
Original extension and institutional publications behind the planting, care, and safety facts on this page.
- Verbascum thapsus (Common Mullein)
North Carolina Extension Gardener Plant Toolbox (NC State Extension). Supports general reference. Checked 2026-06-18.