Annual or perennial herb Stem: erect. Leaves: opposite, oblong to lance- or egg-shaped, toothed, densely hairy with interconnecting veins beneath. Flowers: bluish violet. Fruit: four nutlets surrounded by the persistent calyx.
Similar species: Verbena x rydbergii is a hybrid of Verbena hastata and Verbena stricta. The attributes of the hybrid are intermediate of the parents. It has the habit of V. hastata but the larger flowers and densely hairy and veiny lower leaf surface of V. stricta. See links below for further information on the parents.
Flowering: June to September
Habitat and ecology: Rare in degraded low areas or wet ground, usually in areas with both parents nearby.
Occurence in the Chicago region: native
Etymology: Verbena is the Latin name for vervain. Rydbergii is named after Per Axel Rydberg, an early 20th century expert on the flora of the western United States.