
Onion
- Botanical Name
- Allium cepa var. cepa
- Hardiness
- Annual
- Height
- 1 to 3 feet
- Width
- 6 to 12 inches
- Flowers
- Mid summer: usually doesn't flower unless stressed or grown from sets that are too large
- Fruit
- Yellow, white, or red
- Light
- Full sun
- Soil
- Moist, well-drained, rich
- Planting & Care
- Can be direct seeded in the garden if grown for harvesting as scallions
- Begin sowing when the soil temperature reaches 50°F. Plant seeds 1/4 deep and space 1/2 apart. Thin to 1/2 to 1 inch spacing.
- Can be started from seed indoors 8 to 10 weeks before last frost date. Sow seeds 1/4 deep and 1/2 apart. Harden off and set out in the garden 2 to 4 weeks before last frost date.
- Space transplants 4 inches apart for large bulbs, 2 inches for small bulbs and 1/2 to 1 inch if harvesting as scallions. Space rows 12 to 18 inches apart.
- Transplant sets (young bulbs about 1/2 inch in diameter) 1 inch deep 2 to 4 weeks before last frost date. Space sets 4 inches apart for large bulbs, 2 inches for small bulbs and 1/2 to 1 inch if harvesting as scallions.
- To develop long white stems on scallions, hill the soil around the onions when they grow to 4 inches tall
- Onions require consistent moisture and good weed control
- Mulch to suppress weeds and retain soil moisture
- Problems
- Onion maggot, thrips, botrytis blight
- Varieties
- Stuttgarter - yellow
- Ebenezer - yellow
- Vidalia
- Barletta - white, mild flavor, slightly flattened bulb, 65-70 days to maturity
- Cipollotto da Mazzi - scallion type with long white stock
- Super Star - sweet white, day-length neutral, All-America Selections winner
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