It is an annual or biennial growing to 90 cm (35 in) tall by 30 cm (12 in) broad, with large, coarse, pointed oval leaves with marked serrations. The leaves are hairy, the lower ones long-stalked, the upper ones stalkless.[2] In spring and summer it bears terminal racemes of white or violet flowers, followed by showy, green through light brown, translucent, disc-shaped[2] silicles (not true botanical seedpods). When a silicle is ripe and dry, a valve on each of its sides readily falls off, and its seeds fall off a central membrane which has a silvery sheen, 3–8 cm (1–3 in) in diameter; the membrane can persist on a plant throughout a winter depending on the weather.[3] These silicles are much used in dry floral arrangements.