New York Aster / Symphyotrichum novi-belgii
Like the other asters, New York Aster blooms in fall, but it tends to bloom even later than most and that late blooming supports many native bees in their preparation for winter, including young bumblebee queens before they bed down for the cold season under the leaf litter.
This species is easy to grow from seed, but a word of caution - it is very vigorous and spreads rapidly by rhizomes about an inch below the soil surface. If it is grown out in the garden, we have seen plants reach seven or eight feet tall with strong stems. The safest way to grow this plant is in pots, where it grows to maybe two or three feet tall. It produces quite a number of flowers that you will want to deadhead if you don't want it spreading by seed.
Seed Planting/Germination Key
Storage: Store in a cool, dry, dark place prior to planting.
Rule of thumb for depth of planting: The maximum depth should generally be half the width of the seed, but many wildflower seeds will germinate well if sown on the surface.
Easy: Generally germinates within 5 to 30 days with no need for cold pretreatment. Keep potting mix or soil consistently moist during the germination period.
Cold(30): Germination rates are higher if cold pretreatment applied either by placing the seed within moist paper towel or sand within a refrigerator for 30 days or outside in late winter.
Cold(60): Germination rates are higher if cold pretreatment applied either by placing the seed within moist paper towel or sand within a refrigerator for 60 days or outside in mid-winter.
Cold(90); Outdoors: Germination rates are higher if cold pretreatment applied either by placing the seed within moist paper towel or sand within a refrigerator for 90 days or outside in late fall or early winter. The best route is to plant these outdoors in either a pot or directly on the soil.
Approximate Seeds Per Packet: 100
Germination: Cold(60)
Lifecycle: Perennial
Sunlight: Full, Part
Soil Moisture: Wet, Moist, Medium
Height: 5
Bloom Period: September-November
Bloom Color: White, Purple
USDA Zones: 3-8
Attracts: Bees
Larval Host For: Silvery Checkerspot Butterfly, Pearl Crescent Butterfly