Symphyotrichum lanceolatum
panicled aster
Overview
Symphyotrichum lanceolatum is a rhizomatous herbaceous perennial in the family Asteraceae, forming colonies of upright stems 2-5 feet (60-150 cm) tall and 1-3 feet (30-90 cm) wide. The smooth to sparsely hairy stems carry narrow, lance-shaped leaves 2-6 inches (5-15 cm) long with finely toothed or smooth margins. From late summer into autumn the plant produces many small daisy-like heads 0.5-0.75 inch (1.2-2 cm) across in branched, leafy sprays, each with 16-50 white to pale lavender ray florets around a yellow centre that ages to pink-brown. The seeds are small achenes with bristly tufts that disperse on the wind. Symphyotrichum lanceolatum spreads steadily by creeping rhizomes, forming broad patches in moist meadows and along watercourses. It supplies nectar and pollen to bees, butterflies, and other late-season insects. Limitations include an aggressive rhizomatous habit that can crowd out neighbours and lower leaves that often wither by bloom time.
Native Range
Symphyotrichum lanceolatum is native across much of North America, from Canada south through the United States to the Gulf states and west to the Rocky Mountains. It grows in moist, open habitats including wet meadows, stream banks, ditches, marsh edges, and damp roadsides.Suggested Uses
Symphyotrichum lanceolatum is used in rain gardens, pond and stream margins, wet meadows, and naturalised pollinator plantings, spaced 18-30 inches (45-75 cm) apart. Its spreading habit suits large, informal areas and erosion control on moist ground rather than small, tidy borders.How to Identify
Appearance
Size & Dimensions
Height2' - 5'
Width/Spread1' - 3'
Reaches mature size in approximately 2 years
Bloom Information
Symphyotrichum lanceolatum blooms from late summer into mid-autumn, roughly August to October, with each colony flowering for six to ten weeks. The pale flowers open in tiered sprays along the upper stems. Bloom continues until frost in many regions, supplying late forage for pollinators.
Detailed Descriptions
Flower Description
White to pale lavenderFoliage Description
Medium greenGrowing Conditions
Sun Requirements
Requires 4-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Symphyotrichum lanceolatum grows in full sun to part shade on average to moist, well-drained soil and tolerates damp ground that many perennials dislike. It withstands clay and seasonal flooding but spreads fastest in rich, moist soil. Cutting the stems back by half in early summer produces shorter, sturdier plants. Division every two to three years controls the spreading clumps and renews vigour. Powdery mildew and aster wilt can affect plants in crowded, humid conditions. No fertiliser is needed on average garden soil.Pruning
Symphyotrichum lanceolatum can be cut back by one-third to one-half in late spring or early summer to limit height and reduce flopping. Spent stems are cut to the ground after flowering or left for winter interest and seed-eating birds. Lifting and dividing the clump in spring keeps the colony in bounds.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
late spring