Onion (from sets) plant

When to plant onions in zone 4b

In zone 4b, the last spring frost usually comes around May 8 and the first fall frost around Sep 28. Here is when to plant onions.

Sow in the bedApr 10
Start pickingJul 19

Your onion (from sets) calendar for zone 4b

Plant small bulbs ("sets") pointy end up. Harvest when the tops fall over.

Spacing in a raised bed: 9 plants per square foot.

These dates are estimates from the average frost dates for zone 4b. Your local frost dates may be a week or two different. If a late cold snap is forecast, wait a few days.

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Onions in other zones

See everything to plant in zone 4b →