Asters

Basic Information

Seed Number

138

Seed Name

Asters

Variety

Pompom Constellation

Category

Flower

Plant Family

Asteraceae

Plant Type

Pompon China aster (Callistephus chinensis)

Planting Method

Direct Sow or Transplant

Seed Status

In Seed Bank

Created

2026-08-14 00:50:34

Updated

2026-08-19 15:35:29

Planting Information

Start Planting Date

Mar 10

Last Recommended Planting Date

Jun 15

Plantable Months

March, April, May, June

Indoor Start

Mar 10 – Mar 24

Direct Sow

May 6 – Jun 15

Transplant

May 6 – May 31

Indoor Start Weeks Before Frost

8 weeks

Transplant Weeks After Frost

0 weeks

Germination Days

10–14 days

Harvest/Maturity

Not recorded

Succession Planting

14 days

Growing Conditions

Ideal Soil Temperature

70-72°F

Planting Depth

1/8 in

Plant Spacing

6-12 in

Row Spacing

12-18 in

Thin-To Spacing

6-12 in

Sun Requirements

Full sun to partial shade

Water Needs

Keep consistently moist but well drained

Soil Preference

Fertile, well-drained soil; approximately pH 5.5-7.5

Minimum Container Size

2-3 gal

Plant Height

Not recorded

Perennial/Biennial Status

Annual

Container Friendly

Yes

Trellis/Support Needed

No

Frost Tolerant

No

Heat Tolerant

No

Drought Tolerant

No

Pollinator Friendly

Yes

Medicinal

No

Garden Uses

Companion Planting

Storage

Seed Source/Brand

MSU Extension; Detroit frost dates; Almanac Detroit

Packet Year

Not recorded

Quantity Notes

Not recorded

Purchase Date

Not recorded

Expiration Year

Not recorded

Storage Box

Not recorded

Container

Not recorded

Envelope

Not recorded

Row

Not recorded

Slot

Not recorded

Storage Notes

Not recorded

Notes

Original Planting Method: Start indoors or direct sow
Outdoor / Direct Sow / Transplant Window: May 1 – Jun 20
Days to Harvest / Bloom: 90–120 days to bloom
Medicinal / Herbal Use: Mostly ornamental
Succession / Reusable Notes: Start indoors for earlier blooms.
Zone 6B Notes: Good late-season pollinator flower.
Companion Plants: Calendula, zinnias, marigolds, yarrow, echinacea, herbs, pollinator beds
Avoid Planting Near / Watch Outs: Crowding/wet foliage
Sources: MSU Extension: https://www.canr.msu.edu/resources/garden_planning_calendar | Detroit frost dates: https://www.ufseeds.com/vegetable-planting-calendar-detroit-michigan.html | Almanac Detroit: https://www.almanac.com/gardening/planting-calendar/MI/Detroit

[[RESEARCH ENRICHMENT START]]
Zone 6B: Start indoors about 6-8 weeks before May 5 or direct sow after frost. China asters generally perform best in moderate temperatures.
Germination: Sow shallowly at approximately 70-72°F and maintain even moisture.
Harvest: Harvest pompon blooms when outer florets begin opening for fresh bouquets.
Seed Saving: Allow mature flower heads to dry fully. Nearby China aster cultivars can cross.
Special Care: The exact cultivar name 'Pompom Constellation' could not be verified from a sufficiently reliable current seed listing. Pompon-form Callistephus chinensis culture is used, while cultivar-specific height, maturity and flower measurements are intentionally null.
Research Source: Johnny's Selected Seeds — https://www.johnnyseeds.com/growers-library/flowers/aster/china-aster-key-growing-information.html — China aster germination, spacing, soil requirements, annual lifecycle and harvest
Research Source: NC State Extension Plant Toolbox — https://plants.ces.ncsu.edu/plants/callistephus-chinensis/ — Callistephus chinensis pompom flower forms, pollinator value and variable cultivar sizes
[[RESEARCH ENRICHMENT END]]