Teasels are monocarpic perennials.
The plant grows as a basal rosette for a minimum of one year, then sends up a tall, flowering stalk and dies after flowering. The rosette stage varies according to the amount of time needed to acquire enough resources for flowering to occur. During the rosette stage, leaves change from being somewhat ovoid in the younger stage to large, oblong, and quite hairy in the older stage. During the rosette phase, teasel develops a large taproot. The taproot may be over 2 feet in length and 1 inch in diameter at the crown.