Mullein

Basic Information

Seed Number

53

Seed Name

Mullein

Variety

Not recorded

Category

Medicinal

Plant Family

Scrophulariaceae

Plant Type

Common mullein (Verbascum thapsus)

Planting Method

Direct Sow or Transplant

Seed Status

In Seed Bank

Created

2026-08-14 00:50:34

Updated

2026-08-19 15:35:29

Planting Information

Start Planting Date

Mar 15

Last Recommended Planting Date

Jun 15

Plantable Months

March, April, May, June

Indoor Start

Mar 15 – Apr 15

Direct Sow

Apr 1 – Jun 1

Transplant

May 5 – Jun 15

Indoor Start Weeks Before Frost

Not recorded

Transplant Weeks After Frost

0 weeks

Germination Days

10–21 days

Harvest/Maturity

Not recorded

Succession Planting

Not recorded

Growing Conditions

Ideal Soil Temperature

65-75°F

Planting Depth

Surface sow; do not bury

Plant Spacing

18-24 in

Row Spacing

24-36 in

Thin-To Spacing

18-24 in

Sun Requirements

Full sun; tolerates some shade

Water Needs

Water during establishment; highly drought tolerant once established

Soil Preference

Dry, sandy, rocky or otherwise poor but well-drained soil; does not tolerate wet soil

Minimum Container Size

5 gal

Plant Height

6-10 ft in flower

Perennial/Biennial Status

Biennial

Container Friendly

Yes

Trellis/Support Needed

No

Frost Tolerant

Yes

Heat Tolerant

Yes

Drought Tolerant

Yes

Pollinator Friendly

Yes

Medicinal

Yes

Garden Uses

Companion Planting

Storage

Seed Source/Brand

MSU Extension; Detroit frost dates; Almanac Detroit

Packet Year

Not recorded

Quantity Notes

Not recorded

Purchase Date

Not recorded

Expiration Year

Not recorded

Storage Box

Not recorded

Container

Not recorded

Envelope

Not recorded

Row

Not recorded

Slot

Not recorded

Storage Notes

Not recorded

Notes

Original Planting Method: Start indoors or direct sow; many benefit from cold stratification
Outdoor / Direct Sow / Transplant Window: Apr 15 – Jun 15; Sep 1 – Oct 15 for fall sowing
Germination Time: 10–30+ days
Days to Harvest / Bloom: Blooms/harvest often year 2
Container Friendly: Yes for many; deep-rooted types prefer ground
Succession / Reusable Notes: Great for permanent herb/medicinal beds.
Zone 6B Notes: Many medicinal perennials need patience and may not bloom first year.
Companion Plants: Yarrow, echinacea, calendula, lavender, sage, thyme, oregano, clover, native flowers
Avoid Planting Near / Watch Outs: Crowded/overly wet beds
Sources: MSU Extension: https://www.canr.msu.edu/resources/garden_planning_calendar | Detroit frost dates: https://www.ufseeds.com/vegetable-planting-calendar-detroit-michigan.html | Almanac Detroit: https://www.almanac.com/gardening/planting-calendar/MI/Detroit

[[RESEARCH ENRICHMENT START]]
Zone 6B: Common mullein is a hardy biennial in Zone 6B. The first year forms a basal rosette; the tall flowering stalk develops in the second year.
Germination: Seed requires light. Press onto the surface of moist soil and do not bury deeply. Stratification is not required for ordinary spring germination.
Harvest: Leaves are generally harvested from healthy first-year rosettes or before flowering; flowers can be collected individually as they open.
Seed Saving: Allow seed capsules on the second-year stalk to mature and dry. Each plant can produce a very large quantity of long-lived seed, so collect before widespread dispersal.
Special Care: Can self-seed heavily and become weedy. Rich soil may produce tall weak flower stalks that require staking. Filter herbal preparations carefully because fine leaf hairs can be irritating.
Research Source: NC State Extension Plant Toolbox — https://plants.ces.ncsu.edu/plants/verbascum-thapsus/ — biennial habit, 6-10 foot flower stalk, full sun, dry soil, drought tolerance and poor-soil adaptation
Research Source: Strictly Medicinal Seeds — https://strictlymedicinalseeds.com/product/mullein-common-verbascum-thapsus-seeds-organic/ — common mullein medicinal seed identification and surface sowing without stratification
[[RESEARCH ENRICHMENT END]]