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- Allium cepa, Onion
- Amaryllidaceae family
- Sunlight: full sun.
- Soil conditions: Well-drained, fertile soil.
- Can be planted from seeds, sets, and transplants. Onion bulbing is triggered by day length.
- Short Day varieties form bulbs when day length reaches 10 hours. Can be grown in the North. Intermediate Day varieties form bulbs when day length reaches 12-13 hours. Can be grown in most areas except far North, and Deep South. Long Day varieties form bulbs when day length reaches 14 hours. Grow best in northern areas including Delaware.
- Big Daddy (110 days) Spanish style, yellow onion. Long Day. Good storage onion.
- Walla Walla (80-90 days) Big round onions, sweet, mild, juicy flesh. Long Day.
- Red Candy (95 days) Glossy red, sweet, mild flavor. Intermediate Day.
Common pests & diseases
- Onion Maggot
- Downy Mildew
- Leaf Blight
- Onion Rust
This publication was created by Master Gardeners Rick Judd and Gail Hermenau. Photos courtesy of Gail Hermenau.
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