Harvesting and Drying Mullein: Leaves, Flowers, and Timing

The reward for growing (or carefully foraging) mullein is a jar of your own dried leaf and flower, ready through the cold months when a soothing cup matters most. Harvesting it well is simple, but timing and drying make the difference between fragrant, green-grey leaf and a jar of dull brown crumble. Here is how I do it.

Before you pick a single leaf from the wild, be certain of your plant. Run it past how to identify mullein plant and the mullein look-alikes, since one of them (foxglove) is toxic.

When to harvest mullein

Timing depends on which part you want.

• Leaves: best gathered before the plant flowers, when the leaves are at their lushest and the plant's energy is still in its foliage. The big, clean leaves of the first-year rosette are ideal, as are the lower leaves of a second-year plant before the spike takes over.
• Flowers: gathered through the second summer, picking blooms a few at a time as they open up the spike. They are fiddly and slow to collect, with no harvesting them all at once, but they are prized, especially for the ears and for night-time coughs.

Pick on a dry day, ideally mid-morning once any dew has burned off. Wet leaves are far more likely to mould while drying.

How to harvest

• Choose clean, healthy, unblemished leaves and flowers, and skip anything yellowing, spotted, or chewed.
• Snap or snip leaves cleanly from the stem.
• Take a sensible share and leave plenty behind, both for the plant and, if you are foraging, for the patch and its wildlife.
• A gentle warning: the leaf hairs that irritate the throat can also itch the skin of sensitive folk. If that is you, wear light gloves.

How to dry mullein

The goal is to dry it quickly, in shade, with airflow, because heat and sunlight bleach out the colour and the goodness.

For leaves:

1. Lay them in a single layer on a drying screen, rack, or clean cloth, or hang small loose bundles stem-up.
2. Keep them out of direct sun, somewhere warm, dry, and well-ventilated, such as an airy room, a covered porch, or a shed.
3. Give them space; do not let leaves overlap and trap moisture.
4. They are ready when they crackle and snap rather than bend, usually one to two weeks, depending on your air.

For flowers:

• Dry them in a single layer in the same shaded, airy conditions. They are delicate, so handle gently and check they are fully dry before storing, as their moisture is easy to underestimate.

A dehydrator on its lowest setting works too, if your climate is damp and air-drying risks mould.

Storing your harvest

Once everything is fully crisp:

• Store leaves and flowers in clean, airtight jars.
• Keep them away from heat and light: a cupboard, not a sunny windowsill.
• Label with the date. Dried well and stored right, mullein holds its quality for about a year.

Crumble or cut the leaf as you need it rather than all at once, to keep it fresher for longer.

Straight to the teapot

With a jar of your own dried mullein on the shelf, you are set for the season. When the first scratchy throat arrives, our guide to how to make mullein tea walks through brewing a clean, soothing cup, including the all-important double strain that keeps those leaf hairs out. You can also steep that dried leaf into a mullein tincture that keeps for years. And if you want more plants next year, growing mullein from seed is as easy as scattering and waiting.