Common mullein, also known as wooly mullein, velvet dock, flannel leaf, Aaron's rod, torch plant, and miner's candle is a member of the figwort family.
Originally, Common mullein was brought over from Europe by early settlers. It was used as a medicinal herb in the treatment of coughs and diarrhea and as a respiratory stimulant for the lungs when smoked. A methanol extract from this plant has also been used an an insecticide for mosquito larvae.
A biennial, first year mullein plants are low-growing rosettes about 5 inches in width. The felt-like leaves are a bluish green in color. Flowering plants are produced the second year, growing 5 to 10 feet in height including the flowering spike. This leafy spike produces five-petaled flowers that bloom a few at a time all summer. The tiny seeds can germinate after lying dormant for several decades.
Mullein plants have shallow tap roots and are easily hand-pulled. Recently, weevils (Gymnetron tetrum) that feed on the seeds have been found effective in reducing seed production.
When hand-pulling is not safe or practical, such as on a steep slope, herbicide control is an effective option. This is especially effective during the rosette stage. Because of the wooly nature of the leaves, herbicides should be mixed with a surfactant to facilitate uptake. A 2% solution of glyphosate or triclopyr and water, plus a non-ionic surfactant, can be applied using a hand sprayer. Use with care around desired plants as glyphosate is a non-selective herbicide. Always read and follow the directions carefully when using a herbicide.
Photographs courtesy of Judy Sedbrook.
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010