Mullein

Scatter seed on bare, well drained soil in late spring to early summer and press it against the surface without covering it. Do not rake soil over the top. Expect only a flat rosette this year, the flower stalk comes the season after. Mullein seed will not germinate in the dark, so only seed lying at or near the soil surface ever sprouts, and burying it wastes the sowing. The rosette also needs a winter of cold to trigger flowering the following spring, which is why year one is leaves only.

Walk the patch in spring and pull, hoe or dig unwanted rosettes as soon as they are big enough to hold onto, working when the soil is moist so the taproot lifts whole. Do not reach for the mower or the sprayer. Mowing backfires - the rosettes simply widen and then bolt as soon as mowing stops - and herbicide is a poor tool on this plant because the dense woolly leaf hairs block absorption of the chemical. Hand removal at the rosette stage, before any stalk rises, is what actually works.

Work the spike in the morning and take only the open yellow flowers. Come back every few days all summer rather than waiting for one big pick. Each mullein flower opens before dawn and closes by mid afternoon, and the spike opens only a few flowers at a time in spirals from the bottom upward, so an afternoon pass finds almost nothing open.

Harvest the big basal leaves from the first year rosette across its first summer, cutting outer leaves and leaving the center of the rosette intact to keep feeding the taproot. Mullein is a biennial that dies once it flowers. The rosette leaves are largest and the plant is still alive in year one, while year two pours everything into a flower stalk of roughly 3 to 10 feet and then the plant is gone for good.

Once flowering finishes, cut the whole stalk off at its base and bag it or burn it. Do not leave it standing to dry, and do not compost it in place. Skip this only if you deliberately want volunteers. One plant carries 200 to 300 capsules holding 500 to 800 seeds each, well over 100,000 seeds in total, and that seed stays viable in the soil for decades - seeds in the Beal longevity experiment still germinated after 100 years. Cutting the stalk while the capsules are green is the one moment you control the seed bank.