Seedling
Most milkweed plants emerge from overwintering root buds. These are more robust than seedlings and lack cotyledons. Hypocotyls of seedlings are light green and smooth. Cotyledons are dull green, oval, rounded at the tips (1.2 cm long).
Juvenile plant
Young leaves are opposite, dark green, waxy, oblong, pointed at the apex, with a prominent white midvein on the surface of the leaf. Seedlings do not flower during the first year of growth.
Mature plant
Stems are usually branched, hollow, erect, covered with downy hairs, and exude a milky sap. Stems are green, becoming red later in the season. Leaves are oblong-elliptic to oval, 7-20 cm long, opposite, occasionally whorled, on short petioles (about 8 mm). Leaf blades are green and smooth on the upper surface, with a prominent white midvein, and lighter green and downy hair beneath. Margins are entire; pinnate veins do not reach the leaf margin.
Post senescene
The characteristic pods turn grayish brown and persist on dead stems throughout winter. Pods are shiny yellow on the inside. Some seeds may remain within the pods for an extended period.
