Once a critical and guarded part of the fullering trade, teasel's stiff seedheads were used to brush and tease the nap of woolen fabric. Now that steel carding has replaced this ancient method, teasel has little commercial value and is only used for fulling the finest woolens such as cashmere. Smuggled to America in the 1700's, teasel naturalized here and now ranks as a noxious invasive weed in most of our states.
Start new teasel plantings from seed. Beds can be prepared in the fall and planted in April or May after the last frost. For a fall project, spade or till the ground several inches deep. Cultivate or hoe the soil to break up clods, and then rake the bed smooth. Scatter a light mulch over the bed to encourage earthworm activity during the cooler months.
Plant new beds in early spring by broadcasting seeds thinly over the ground and raking the surface. Teasel easily self-seeds on bare ground, so keep the planting shallow. Covering with a light hay mulch prevents the surface from drying out between waterings. Teasel grows naturally in crowded stands. Thinning to several inches apart creates vigorous plants.
Winterize the teasel bed the first season by pulling out competing weeds. Teasel will not flower the first year, instead forming rosettes of spiky leaves and deep dandelion-like roots. If foliage is not disturbed, the leaves form a natural cover for the root crowns during cold weather. Covering the teasel with mulch isn't absolutely necessary, but a light mulch will contribute to soil health.
For the second winter leave the seedstalks in place until the weather and wildlife have scattered the seeds. Biennial in habit, teasel blooms and dies in the second year of growth. Cut out dead stalks to improve the appearance of the bed, but leave the old plants in place. As mature plants die, the old stalks and leaves provide cover through the winter for dropped seed and become mulch for new teasel seedlings in the coming spring. Self-seeding will maintain the bed if the natural process is encouraged.