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When to plant onion in Ohio

Ohio spans USDA zones 6a–7a, so the right time to plant onion shifts by weeks across the state. The window to transplant seedlings outdoors runs from about March 11 in Cleveland to April 10 in Warren — below are local dates for 187 cities, each computed from its own frost dates.

In Columbusthe onion transplant out window (March 23–April 6) has passed for this year.
CityZoneLast frostFirst frostTransplant out
Columbus6bApril 20October 24March 23 – April 6
Cleveland7aApril 8November 12March 11 – March 25
Cincinnati6bApril 16October 25March 19 – April 2
Toledo6bApril 20October 27March 23 – April 6
Akron6bApril 24October 28March 27 – April 10
Dayton6bApril 18October 25March 21 – April 4
Parma6bApril 20November 3March 23 – April 6
Canton6bApril 24October 26March 27 – April 10

Onion in Ohio: FAQ

When can I plant onion in Ohio?

Across Ohio, the time to transplant onion spans roughly March 11 in Cleveland to April 10 in Warren, each following that city's local frost dates.

Does the onion planting date vary across Ohio?

Yes. Ohio publishes 187 cities with their own frost dates, so the right onion planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.

How long does onion take to grow in Ohio?

Onion takes about 90–110 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.

Planting reminders

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An email when it’s time to start seeds, transplant, and sow — timed to your frost dates. Double opt-in, one-click unsubscribe, no spam.

Onion planting guide →All Ohio cities →Ohio planting calendar →
When to Plant Onion in Ohio — Frost-Based Dates by City — BlissGarden