Prairie Gerardia, Prairie Agalinis, Prairie False Foxglove

Agalinis heterophylla (Nutt.) Small ex Britt. & A. Br.

Scrophulariaceae (Figwort family)


Prairie Gerardia is a native, warm-season annual in the Figwort family with narrow, needle-like leaves. It is also commonly named Prairie Agalinis or grass killer because it can shadow and suppress lower-growing grass. The plant grows from 1 to 3 feet or 0.3 to 0.9 m tall. A key characteristic of Prairie Gerardia is that its stems turn black when the plant dies in the summer or fall. Once the seeds break open, the wind can carry the small seeds a long distance to reseed and reproduce. Depending on the available moisture, the flowers appear during the summer or in the fall and bloom for around one month. The flowers are purple to pink in color and tubular in shape. The forage value of this plant is low for livestock and fair for wildlife. It is a larval host for the Buckeye butterfly and attracts a variety of other pollinators, including Bumblebees.


Prairie Gerardia is found mainly on prairies, plains, grasslands, open woodlands, and fallow fields. Requires part shade.