Common mullein - Verbascum thapsus L. - Plant & Pest Diagnostics

The photo is of a common mullein plant. The plant has a tall yellow flower on a terminal spike. The leaves are green, oblong, and covered with dense hairs on both sides.

Common mullein - Verbascum thapsus L.

Verbascum thapsus L.

Scrophulariaceae - Figwort family

MI Status

Non-native

Life cycle

Biennial.
The first-year plant is a basal rosette. The second-year rosette produces an erect flowering stem.

Leaves

Rosette leaves are covered with dense hairs on both sides. They feel soft like wool. They are oblong and up to 15 inches long. Leaves on the second-year stems are also woolly but are much smaller than the rosette leaves. They lack petioles and are attached alternately to the stem. The upper leaf edges can be entire or bluntly toothed and decrease in size as they progress up the stem.

Stems

Stems are single, densely hairy, and mainly unbranched. On occasion, the stem may branch and produce smaller flower spikes in addition to the main terminal spike. Stems can appear winged due to leaf bases running down the stem. Dead stems can persist for more than a year.

Flowers and fruit

The flower is a terminal spike. It is packed with flowers that have fused yellow petals with 5 lobes. They are saucer-shaped and are less than 1 inch in diameter. The fruit is a rounded, downy capsule that is about ¼ inch in diameter. The capsule is 2-celled and filled with numerous dark brown seeds. The seeds have wavy ridges.

Reproduction

Seeds.

The photo is of a first year plant that is a basal rosette. The leaves are oblong and covered with dense hairs on both sides. — Common mullein rosette

The photo is a close up of a common mullein leaf. It has a prominent white midvein. The leaves lack petioles and are attached alternately on the stem. They are covered with dense hairs. — Common mullein leaf

The photo is of a young common mullein in its second year. This plant is producing an erect flowering stem. You can see the older oblong leaves as well as some newer smaller leaves emerging. — Common mullein

Th photo is of a common mullein flower. It is on a terminal spike and is packed with flowers that have fused yellow petals with five lobes. — Common mullein flower

Accessibility Questions:

For questions about accessibility and/or if you need additional accommodations for a specific document, please send an email to ANR Communications & Marketing at anrcommunications@anr.msu.edu.

Plant & Pest Diagnostics