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Onion roots in the soil



General information

  • Scientific Name: Allium cepa
    • Family: Alliaceae, Amaryllidaceae
  • Cool season
  • Planting Window: mid-March to mid-April
  • pH = 5.5-7.0
  • Planting Depth:
    • Seeds: 1/2 inch, direct sow in soil
    • Sets: lay in hole, roots down, cover with soil half way up the bulb
  • MPD: 3 inches (in both directions)
  • Can be companion planted with cabbage family members, beets, tomatoes and lettuce
  • Tip: onions like rich, composted soil!

Pests and diseases

  • Onion maggot - use floating row covers to prevent flies from infesting plants

Successful cultivars and harvest

  • Cultivars:
    • Seeds: White Lisbon Bunching (60 days)
    • Sets: available sets Stuttgarter
  • To harvest, pull from ground when tops are brown
  • Harvest green onions mid-May through late June; harvest large onions late July through late August
  • If storing onions, allow tops to wilt, cut off 1-2 inches above bulb and dry for one week

This publication was created by Master Gardener Rick Judd and designed by Extension Scholar Taylor Trent. Photos courtesy of Rick Judd.

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