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!

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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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