Species Native to Missouri
Common Name: blue wood aster
Type: Herbaceous perennial
Family: Asteraceae
Native Range: Eastern and central North America
Zone: 3 to 8
Height: 2.00 to 5.00 feet
Spread: 1.50 to 2.00 feet
Bloom Time: August to September
Bloom Description: Pale blue to rich blue with yellow centers
Sun: Full sun to part shade
Water: Dry to medium
Maintenance: Low
Suggested Use: Naturalize
Flower: Showy
Attracts: Butterflies
Culture
Easily grown in average, dry to moist, well-drained soils in full sun to part shade. Usually found in part shade locations. Tolerates shady conditions well. Prefers moist, rich soils, but avoid consistent moisture. Good air circulation helps reduce incidence of foliar diseases. Pinching back stems several times before mid-July will help control plant height, promote bushiness and perhaps obviate the need for staking. Easily grown from seed and often abundantly self-seeds in the garden if not deadheaded. Plants may be cut to the ground after flowering to prevent unwanted self-seeding and/or to remove unsightly foliage.
Noteworthy Characteristics
Symphyotrichum cordifolium, commonly known as heart-leaved aster or blue wood aster, is a somewhat weedy, herbaceous perennial that is native to rich, dry to moist woodlands, forest margins, fields, dry meadows, bluff bases and stream banks in eastern to central North America from Quebec to Manitoba south to Kansas, Arkansas and Florida. It is a stout, leafy plant that typically grows on smooth, branched, upright-arching stems to 2-5’ tall. Stems are topped by dense, small-leaved panicles of daisy-like asters (each flower to 3/4” diameter) which bloom late summer to fall (late August to October). Flowers feature pale blue to rich blue rays and yellow centers. Flowers are attractive to butterflies. Leaves are sharply-toothed, with the lower ones being heart-shaped (to 5” long), hence the specific epithet and common name references to heart-shaped leaves. The upper leaves are smaller and more ovate.
This heart-leaved aster was formerly known as Aster cordifolius.
Similar species to S. cordifolium are Symphyotrichum sagittifolium (arrow-leaved aster), Symphyotrichum urophyllum (white arrow-leaved aster) and Symphyotrichum drummondii (Drummond’s aster).
Genus name comes from the Greek symph meaning coming together and trich meaning hair in possible reference to the flower anthers.
Specific epithet means with heart-shaped leaves.
Problems
No serious insect or disease problems. Some susceptibility to powdery mildew, leaf spots and rust. Aster wilt can also be an occasional problem, particularly if plants are grown in poorly-drained clay soils. Taller plants may require staking or other support. Foliage tends to decline by late summer.
Uses
Open shade gardens, native plant gardens, cottage gardens or butterfly gardens.