Smooth Blue Aster


Growing 30–100 cm high, smooth blue aster is common through the prairies. Numerous flower heads, 2–3 cm across with 20 or more blue ray florets, form a branched cluster at the end of the stout, hairless stems. The thick, hairless leaves often have a whitish bloom.

Although people can develop allergic rashes after contact with asters, some First Nations people used a smoke smudge of smooth blue aster to revive the unconscious and in sweat baths. (Wilkinson 251)


Growth habit and range: This erect, perennial herbaceous plant is commonly found on moist, open sites throughout the prairie and parkland of the province. It grows to a height of 30–120 cm. 

Description: The leaves are alternately placed on the stem, and are a dark, blue-green colour with a whitish, waxy bloom. The leaves are oval to oblong in shape and up to 15 cm long. The leaf margin is smooth to toothed. The lower leaves display winged leaf stalks, and the upper leaves clasp the stem. The flowers appear from July to September and form loose clusters on the upper stems. Each flower is comprised of 20 or more purple to blue ray florets measuring 1 cm in length, and a central disk of yellow to red tubular florets. Overall, each flower measures 2–3 cm in diameter. The fruit is a 3mm long, flattened achene of brown colour, with a bristly pappus.


  • Wilkinson, Kathleen. 1999. Wildflowers of Alberta: A Guide to Common Wildflowers and Other Herbaceous Plants. University of Alberta Press and Lone Pine Publishing, AB.