How to Grow Silky Aster
Silky Aster
Symphyotrichum sericeum
flowerSilky aster is a native North American wildflower characterized by its delicate, daisy-like purple or lavender flowers with yellow centers. The plant grows in low, compact mounds covered with fine, silky-textured foliage that gives it its common name. It blooms in late summer and fall, attracting pollinators and providing valuable late-season color in gardens.
When should you plant Silky Aster in your zone?
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Example Silky Aster timeline · Pittsburgh, PA (Zone 6b)
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Plant Silky Aster
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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First Silky Aster blooms
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Silky Aster dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Zones 4-8, with good performance in zones 3-9
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Seedling
3-4 weeksTiny green seedlings with narrow cotyledons emerge and develop first true leaves with fine, silky texture.
Keep soil consistently moist but not waterlogged. Provide bright light. Thin seedlings to proper spacing to avoid damping off.
Vegetative Growth
6-10 weeksPlant develops compact, mounding form with increasingly silky, fine-textured foliage. Stems remain low and bushy.
Water moderately during dry spells. Begin reducing water frequency as plant matures. Mulch lightly to retain moisture without promoting excessive growth.
Budding
2-4 weeksPurple buds form at branch tips in late summer. Plant reaches mature height of 12-24 inches depending on variety.
Reduce watering further. Do not fertilize or plant may become leggy. Support tall varieties if needed in windy locations.
Flowering
8-12 weeks (late August through November)Abundant 1-inch purple, lavender, or pink daisy-like flowers with yellow disk centers bloom prolifically.
Deadhead spent flowers to encourage continued blooming. Provide water only during extended drought. No fertilizer needed.
Senescence/Seed Set
4-8 weeksFlowers fade to papery texture; seeds develop in central disk. Foliage may turn bronze or reddish in cool fall weather.
Leave plant standing through fall for wildlife benefit and winter interest. Collect seeds if desired before they disperse. Cut back in early spring after frost danger passes.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with strong water stream; use insecticidal soap if severe. Encourage beneficial insects like ladybugs.
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Increase humidity by misting; use miticide spray if infestation is heavy. Avoid excessive nitrogen fertilizer.
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Ensure good air circulation; water at soil level only. Apply sulfur or neem oil if needed. Remove infected leaves.
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Hand-pick early morning; use Japanese beetle traps away from planting area. Avoid carbaryl pesticides.
Uses
Edible flowers
CulinarySilky aster flowers are edible and can be used as garnishes in salads or desserts, adding delicate purple color and a slightly bitter, floral flavor. [source]
Pollinator support
WildlifeLate-season blooms provide crucial nectar and pollen for pollinators including bees, butterflies, and other beneficial insects during fall migration and preparation for winter. [source]
Cut flowers and dried arrangements
HouseholdFlowers dry well and can be used in fresh arrangements or dried bouquets, maintaining color and form for months with proper drying. [source]
Garden design and landscaping
CraftNative cultivar ideal for xeriscaping, cottage gardens, prairie plantings, and pollinator gardens. Provides late-season color with minimal maintenance. [source]
Traditional herbal use
MedicinalNative American traditional uses included the plant for various medicinal purposes; modern herbalists sometimes include aster species in herbal preparations, though scientific evidence is limited. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Cut flowers for fresh bouquets in the morning after dew dries. Flowers are long-lasting in water. For seeds, allow flowers to dry on plant, then collect seed heads in fall and store in cool, dry place. Deadhead regularly to extend blooming period.
Fun Facts
- 🌱 Silky aster is native to the western and central United States, particularly the Great Plains and Rocky Mountain regions, and thrives in the challenging dry, sandy soils of its native habitat.
- 🌱 The fine, silky texture of its foliage and stems is an adaptation to its native dry climate, helping the plant reduce water loss and reflect intense sunlight.
- 🌱 Aster flowers were traditionally used by Native Americans and settlers, and the name 'aster' comes from the Greek word for 'star,' referring to the star-like flower shape.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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