Plants sparsely to densely hispid, glabrous, or glabrate. Stems (3-)4-10(-12) dm, pubescent or, rarely, glabrate. Basal leaves: petiole (1.5-)3-10(-17) cm; blade broadly cordate to narrowly cordate-ovate, (1.5-) 3-12(-18) × (1-)2-8(-12) cm, base cordate, often pubescent. Cauline leaves similar to basal, petiole shorter (distal sessile); blade (proximal opposite, distal alternate), smaller distally. Fruiting pedicels (7-)10-15 mm, glabrous or pubescent. Flowers: sepals (5-)6-9 (-10) × 1-2 mm; petals (15-)17-25(-30) × 5-10 mm, claw 5-10 mm; filaments 5-8 mm; anthers oblong, 2-3 mm; gynophore relatively slender, 7-18 mm. Fruits 3-4.5(-5) × 2-3(-3.5) cm, strongly latiseptate; valves each rounded basally and apically; replum glabrous or sparsely ciliate; style 4-10 mm. Seeds grayish brown, (6-)7-10(-12) × 5-9 mm. 2n = 30.
Flowering Apr-Jun. Roadsides, waste grounds, railroad embankments, thickets, woods, pasture margins; 0-1000 m; introduced; B.C., Man., N.S., Ont., Que.; Calif., Conn., Del., Idaho, Ind., Ky., Md., Mass., Mich., N.Y., Ohio, Oreg., Pa., R.I., Utah, Vt., Wash.; Europe; introduced also in South America (Argentina).
Lunaria annua is cultivated for its attractive flowers but especially for the infructescences, which are used in dry bouquets after removal of the fruit valves and seeds.
Annual herb to 1 m tall Stem: stiffly hairy. Leaves: alternate, short-stalked or stalkless, heart-shaped or triangular- heart-shaped, sharp-toothed. Flowers: in branched clusters. Petals four, purple, to 2 cm wide, bases narrowed, tips broadly rounded. Fruit: a pod, 3.5 - 5 cm long, two-thirds as wide, broadly elliptic, rounded at both ends, flattened, papery.
Similar species: No information at this time.
Flowering: late April to early June
Habitat and ecology: Introduced from Europe. This garden escape has spread to become rather frequent in the eastern sector of the Chicago Region. There are now large quantities between North and Middle lakes near Stevensville in Berrien County, Michigan. Look for this weed in a variety of disturbed areas.
Occurence in the Chicago region: non-native
Etymology: Lunaria derives from the word luna, which refers to the moon-shaped fruit. Annua means annual.
Annual to 1 m; cauline lvs short-petioled or sessile; fls 2 cm wide; frs broadly elliptic, rounded at both ends, 3.5-5 cm, two-thirds as wide; 2n=30. Native of se. Europe, occasionally escaped from cult. May, June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.