Smooth Aster vs Water Arum - TreeTime.ca

Smooth Aster vs Water Arum

Symphyotrichum laeve

Calla palustris

NOT AVAILABLE THIS SEASON - MIGHT RETURN

CUSTOM GROW

Smooth Aster
Water Arum

Smooth Aster is a native perennial wildflower known for its violet-blue, daisy-like flowers. They bloom later in the season, from late summer to early fall. The flowers attract a variety of pollinators, including bees, butterflies, and other beneficial insects. It also serves as a host plant for the Silvery Checkerspot (Chlosyne nycteis) and Pearl Crescent (Phyciodes tharos) butterflies, further enhancing its ecological value. This easy-to-grow wildflower is well suited for native wildflower gardens, pollinator gardens, and naturalization projects.

The Smooth Aster’s non-aggressive root system allows it to spread slowly, and it is more likely to reproduce by seed, which can be controlled through deadheading. As a perennial, it dies back to the crown each winter, it will regrow from the base in the spring. Avoid disturbing the crown during late winter to ensure healthy growth the following season.

Water Arum is a native perennial wetland plant known for its showy white oval sheaths (spathe) that surround a yellow-green, cylindrical flower spike (spadix). It has large, oblong, heart-shaped leaves on stems that rise above the water from shallow, spreading rhizomes. The blossoms are followed in late summer by tiny, pear-shaped fruits that ripen to bright red, adding ornamental interest to wet habitats.

Water Arum provides food for birds and small mammals that eat its berries, and its flowers attract pollinators. It can tolerate cold climates and forms colonies in shallow water and saturated soils. It is well-suited for ecological restoration, riparian planting, naturalisation, and habitat projects in wet and shaded environments.

Smooth Aster Quick Facts

Water Arum Quick Facts

Zone: 3a
Zone: 1b
Height: 0.9 m (3 ft)
Height: 0.2 m (0.8 ft)
Spread: 0.6 m (2.0 ft)
Spread: 0.2 m (0.8 ft)
Light: partial shade, full sun
Light: shade, partial shade
Moisture: dry, normal
Moisture: wet
Growth rate: very fast
Growth rate: medium
Life span: short
Life span: short
Growth form: colony-forming
Spreading: rhizomes - medium, seeds - low
Suckering: none


Toxicity: toxic if ingested
Flowers: purplish-blue; daisy-like
Flowers: white sheath around and yellow spike
Bloom time: late summer to early fall
Bloom time: spring to summer
Berries: red, in clusters
Hybrid: no
Hybrid: no
Catkins: no
Catkins: no


Native to: AB, BC, SK, MB, ON
Native to: AB, BC, SK, MB, ON, QC, NS, NB, NL, YT, NT, PE
Other Names: glaucous aster, smooth blue aster
Other Names: bog arum, swamp lily, wild calla, wild dragon