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Onions in a bumdle

Onions

 

General information

  • 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.
A thumbnail of the onions factsheet
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Successful cultivars

  • 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
  • Leafminers
  • Thrips
  • 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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