How to Grow Mullein
Wikimedia Commons
Mullein
Verbascum thapsus
herbMullein is a tall biennial herb with large, soft, felty leaves and towering spikes of yellow flowers that can reach 3-6 feet in height. Native to Europe and western Asia, it has naturalized across North America and is valued for both ornamental and medicinal purposes. The entire plant is covered in fine hairs, giving it a distinctive woolly appearance.
When should you plant Mullein in your zone?
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Example Mullein timeline · Pittsburgh, PA (Zone 6b)
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Plant Mullein
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Mullein
Late summer into fallBefore the first fall frost (≈ Nov 8)
Sample dates for Pittsburgh, PA. Sign up to get exact Mullein dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; extremely cold and heat tolerant
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Get my Mullein timeline →Growth Stages
Seed Germination
2-4 weeksTiny seedlings emerge with cotyledons; very slow initial growth
Keep soil lightly moist; ensure adequate light exposure; thin seedlings to proper spacing
Rosette Formation (Year 1)
8-12 monthsPlant develops a basal rosette of large, fuzzy, gray-green leaves that spread 12-24 inches across
Water during dry spells; no fertilizer needed; mulch lightly if desired; remove competing weeds
Bolting (Early Year 2)
4-8 weeksCentral flower stalk emerges and rapidly elongates, reaching full height of 3-6 feet
Stake tall varieties in windy locations; discontinue fertilizing; maintain consistent water during this phase
Flowering
6-10 weeksDense spike of bright yellow flowers opens progressively from bottom to top; flowers are 1 inch wide
Deadhead spent flowers to extend bloom; stake if needed; flowers attract pollinators and beneficial insects
Seed Maturation & Senescence
4-8 weeks until frostFlowers fade and develop seed pods; foliage begins to yellow and decline; plant prepares to die back
Leave plants standing to allow self-seeding if desired; collect seed pods before they shatter; plant will naturally die after setting seed
Common Pests
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Hand-pick caterpillars; use neem oil or spinosad if infestation is severe; generally not a major problem in gardens
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Spray with water to dislodge; use insecticidal soap if severe; improve air circulation around plants
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Use yellow sticky traps; spray with neem oil or insecticidal soap; encourage beneficial insects
Uses
Respiratory support tea
MedicinalMullein leaf tea has traditionally been used to soothe coughs, sore throats, and congestion. The mucilage-rich leaves are believed to coat and calm respiratory passages. [source]
Herbal ear oil
MedicinalMullein flowers infused in oil have been traditionally used as a folk remedy for ear discomfort. The anti-inflammatory properties of the flowers make them valued in herbal preparations. [source]
Natural torches and tinder
HouseholdThe fuzzy seed stalks and dried flower spikes were historically soaked in tallow or fat and used as rustic torches. The fibrous texture makes them excellent natural tinder for starting fires. [source]
Natural dye
CraftThe flowers produce a pale yellow or greenish dye used historically in textile dyeing. The soft leaves have also been used as felting material. [source]
Pollinator and beneficial insect support
WildlifeMullein flowers are highly attractive to bees, butterflies, and other pollinators. The plant also hosts beneficial insects and provides shelter for small creatures. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest leaves in the first year during summer and early fall for maximum potency; pick flowers individually as they open for fresh use or drying; collect seed pods in late summer before they split, or allow to self-seed; cut entire flower stalk and hang to dry for seeds; dry leaves and flowers in a warm, well-ventilated area for 1-2 weeks
Fun Facts
- 🌱 Mullein is so drought tolerant and adaptable that it often self-seeds in disturbed areas, abandoned lots, and along roadsides, earning it the nickname 'nature's resilient pioneer plant.'
- 🌱 The fuzzy, soft leaves of mullein inspired the common name 'flannel plant' in some regions, and were historically used as a natural substitute for toilet paper by travelers and outdoorspeople.
- 🌱 A single mullein plant can produce up to 100,000 seeds, which remain viable in the soil for decades and can germinate only when conditions are ideal, creating dramatic 'flowering events' years after the original plant has died.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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