Flower:

Single, stalked flowers in the leaf axils of the upper stem and side branches. Flowers are pink to purple, ¾ to 1 inch long, tubular with 5 round lobes that have a fringe of short hairs along the edge. The 2 upper lobes are slightly smaller than the lower 3 and are often barely spreading. The tube throat is pale pink to white with reddish spots; 4 pale-tipped stamens barely extend out of the tube. Outer surfaces are covered in short, fine hairs, the inner surfaces are hairless or nearly so.

The calyx has 5 triangular lobes that are shorter than the calyx tube, on a slender, nearly erect stalk that is longer than the calyx.

Leaves and stems:

Leaves are linear, stalkless, erect to ascending, 1 to 1½ inches long and about 1mm wide, the toothless edges typically rolled under, the upper surface covered in short, stiff hairs, the lower surface hairless. Leaves are opposite on the main stem, may be alternate on branches, and there are often small leaf clusters in the axils. Stems are angled and rough from sparse, short, stiff hairs. Branches are ascending to nearly erect.

Fruit:

Fruit is a cylindrical capsule about 1/3 inch long, rounded at the tip, and longer than the calyx. Inside the capsule are many dark seeds. The flower stalk elongates to about ¾ inch in fruit.

Notes:

While not considered a rare species in Minnesota, Rough False Foxglove is not commonly encountered, perhaps because it does not produce colonies and tends to get lost in surrounding vegetation unless the spot of color from the showy flowers catches one's eye. A robust plant may be near 2 feet tall, many-branched with many flowers, but those we encountered were under a foot tall with only a few flowers open at a time. The Agalinis species may all appear similar, but can be distinguished by combinations of characteristics. Rough False Foxglove is a species of dry, sandy prairie, with linear, rough textured leaves, flowers on mostly erect stalks in the leaf axils, and fruits distinctly longer than the calyx. By comparison, Purple False Foxglove (Agalinis purpurea) and Slender-leaved False Foxglove (Agalinis tenuifolia) are found in moist to wet habitats, the rare Round-stemmed False Foxglove (Agalinis gattingeri) is hairless to slightly rough textured, with single flowers primarily just at branch tips, and the even rarer Eared False Foxglove (Agalinis auriculata) has broader leaves with a pair of lobes at the base.