Onion
Seed # 220
Basic Information
- Seed Number
- 220
- Seed Name
- Onion
- Variety
- Cipollini
- Category
- Vegetable
- Plant Family
- Amaryllidaceae
- Plant Type
- Cipollini bulbing onion (Allium cepa)
- 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
- Feb 10
- Last Recommended Planting Date
- May 15
- Plantable Months
- February, March, April, May
- Indoor Start
- Feb 10 – Feb 24
- Direct Sow
- Mar 15 – Apr 15
- Transplant
- Apr 15 – May 15
- Indoor Start Weeks Before Frost
- 12 weeks
- Transplant Weeks After Frost
- Not recorded
- Germination Days
- 7–14 days
- Harvest/Maturity
- Not recorded
- Succession Planting
- Not recorded
Growing Conditions
- Ideal Soil Temperature
- Not recorded
- Planting Depth
- 1/4-1/2 in
- Plant Spacing
- 1/2-4 in depending on desired bulb size
- Row Spacing
- 12 in
- Thin-To Spacing
- Not recorded
- Sun Requirements
- Full sun
- Water Needs
- Maintain consistent moisture while bulbs develop
- Soil Preference
- Fertile, loose, well-drained soil
- Minimum Container Size
- 8–10+ in deep
- Plant Height
- Not recorded
- Perennial/Biennial Status
- Biennial
- Container Friendly
- Yes
- Trellis/Support Needed
- No
- Frost Tolerant
- Yes
- Heat Tolerant
- No
- Drought Tolerant
- No
- Pollinator Friendly
- Yes
- Medicinal
- No
Garden Uses
Container Culinary Pollinator Seed SavingCompanion Planting
| Plant | Relationship | Notes |
|---|---|---|
| Broccoli | Good Companion | Not recorded |
| Radish | Good Companion | Not recorded |
| Radish | Good Companion | Not recorded |
| Radish | Good Companion | Not recorded |
| Radish | Good Companion | Not recorded |
Storage
- Seed Source/Brand
- Hudson Valley Seed; Johnny's Selected Seeds; MSU Extension
- 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 early or direct sow in cool spring soil
Outdoor / Direct Sow / Transplant Window: Transplant/direct sow about Mar 25 – May 1
Germination Time: About 7–14 days
Days to Harvest / Bloom: About 100–110 days
Container Friendly: Yes, 8–10+ in deep
Pollinator Friendly: Low when harvested; second-year flowers attract pollinators
Medicinal / Herbal Use: Culinary onion
Perennial?: Biennial botanically; grown as an annual bulb crop
Succession / Reusable Notes: One spring sowing is normally enough; harvest/cure when tops mature.
Zone 6B Notes: Start early for full-sized flattened bulbs before fall. Long-day conditions in Michigan are suitable.
Companion Plants: Carrots, beets, lettuce, cabbage-family crops and tomatoes
Avoid Planting Near / Watch Outs: Keep weed-free and evenly watered during bulb development. Avoid waterlogged soil.
Sources: Hudson Valley Seed: https://hudsonvalleyseed.com/products/borettana-cipollini | Johnny's Selected Seeds: https://www.johnnyseeds.com/growers-library/vegetables/onions/cipollini-mini-specialty-onions-key-growing-information.html | MSU Extension: https://www.canr.msu.edu/resources/garden_planning_calendar
[[RESEARCH ENRICHMENT START]]
Zone 6B: Cipollini onions are well suited to northern latitudes. Smaller bulbs can be produced by close spacing; wider spacing produces larger flattened onions.
Germination: Start indoors early or direct sow in early spring.
Harvest: Harvest when bulbs have flattened to their characteristic shape and tops begin to fall. Cure before storage.
Seed Saving: Allium cepa is biennial and crosses with other flowering A. cepa onions.
Special Care: Cipollini describes a class of small flattened Italian onions rather than one specific cultivar. Yellow, red and other named strains differ substantially in maturity, so exact maturity is intentionally null.
Research Source: Johnny's Selected Seeds — https://www.johnnyseeds.com/growers-library/vegetables/onions/cipollini-mini-specialty-onions-key-growing-information.html — cipollini adaptation to northern latitudes, early-spring direct sowing, 1/4-1/2 inch depth and close-spacing culture
Research Source: Urban Farmer — https://www.ufseeds.com/product/cipollini-yellow-onion-seeds/ONCY.html — Yellow Cipollini as one documented Allium cepa type and evidence of 120-day cultivar variation
Research Source: Botanical Interests — https://www.botanicalinterests.com/products/flat-of-italy-bulb-onion-seeds — Flat of Italy Cipollini as a separate 70-day cultivar, demonstrating why generic Cipollini maturity cannot safely be assigned
[[RESEARCH ENRICHMENT END]]