How to Grow New York Aster Treasure
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New York Aster Treasure
Symphyotrichum novi-belgii 'Treasure'
flowerNew York Aster Treasure is a compact, bushy cultivar of New York aster that produces masses of semi-double purple flowers with golden yellow centers. This autumn-blooming perennial is a favorite for borders, containers, and cut flowers, thriving in cooler climates. It typically grows 18-24 inches tall and flowers prolifically from late summer through fall.
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Example New York Aster Treasure timeline · Pittsburgh, PA (Zone 6b)
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Plant New York Aster Treasure
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 New York Aster Treasure blooms
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact New York Aster Treasure dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives best in zones 4-7; cold-hardy and excellent for northern gardens
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Seedling
2-3 weeksTiny seedlings with first true leaves appearing 7-10 days after germination. Very delicate with fine foliage.
Keep soil lightly moist; maintain bright light without direct heat. Avoid damping off by ensuring good air circulation.
Vegetative Growth
6-8 weeksPlant develops bushy, compact form with increasing leafy growth. Stems become sturdy and the base widens significantly.
Pinch back growing tips in early summer (before July) to promote bushiness and more flowers. Fertilize every 2-3 weeks with balanced fertilizer.
Bud Formation
3-4 weeksFlower buds begin forming at stem tips in late summer. Plant is full and dense with visible bud clusters.
Continue watering consistently. Reduce nitrogen fertilizer and switch to phosphorus-rich formula to encourage blooming. Support with stakes if needed.
Flowering
8-12 weeksSemi-double purple flowers with golden centers open prolifically. Plant is covered with blooms from late August through October and beyond.
Deadhead spent flowers to encourage continuous blooming. Ensure consistent moisture. Enjoy as cut flowers or leave for pollinators.
Decline & Dormancy
Variable by regionFlowering slows as temperatures drop below freezing. Foliage may yellow or brown. Plant enters winter dormancy.
Cut back dead foliage in late fall or early spring. Do not over-water. Mulch around base with 2-3 inches of organic material for winter protection.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Ensure good air circulation; avoid overhead watering. Apply sulfur spray or neem oil if severe. Remove affected leaves.
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Control leafhopper vectors with insecticidal soap. Remove and destroy infected plants. No cure; prevention is key.
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Hand-pick in early morning or use beetle traps away from plants. Apply neem oil or spinosad if infestation is heavy.
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Increase humidity; spray with water to dislodge. Apply miticide or neem oil if population is high.
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Spray with insecticidal soap or strong water spray. Encourage beneficial insects like ladybugs.
Uses
Edible Flowers
CulinaryWhile not commonly eaten, aster petals are edible and can be used as garnish for salads or desserts. They add a slightly bitter, herbal flavor and visual appeal. [source]
Cut Flowers & Arrangements
HouseholdExcellent cut flower with long vase life, perfect for fall bouquets, floral arrangements, and late-season displays. The abundant semi-double blooms create full, lush arrangements. [source]
Pollinator Support
WildlifeA crucial autumn nectar and pollen source for bees, butterflies, and other pollinators during migration and preparation for winter. Provides essential food when many other flowers have finished blooming. [source]
Traditional Herbal Use
MedicinalIn folk medicine, asters have been used to make teas for respiratory support and general wellness, though scientific evidence is limited. Historically valued in traditional Chinese and Ayurvedic medicine. [source]
Dried Flowers & Pressing
CraftDries well for dried flower arrangements and pressing projects, retaining color and form. Creates attractive autumn crafts and decorative dried bouquets. [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 in early morning when stems are fully hydrated for best vase life (7-10 days). Harvest when flowers are fully open but before centers turn dark. Cut at least one-third of the stem length. Leave at least 6 inches of stem on the plant to allow regrowth.
Fun Facts
- 🌱 The name 'aster' comes from the Greek word for 'star,' referring to the star-like arrangement of petals around the flower's center. New York Aster has been New York's state flower since 1951.
- 🌱 New York Asters were traditionally associated with autumn and were used in Victorian flower language to symbolize patience and elegance. The 'Treasure' cultivar was specifically bred for its compact habit and exceptional flower production.
- 🌱 Asters bloom late in the season when most other garden flowers have faded, making them invaluable for extending the garden's flowering period into November in northern regions. A single mature plant can produce hundreds of flowers.
Gardening Terms
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