FrostCal

When to Plant Onions in District of Columbia

In a typical District of Columbia location, start seeds indoors Jan 18 – Feb 1, then transplant outdoors Mar 1 – Mar 15. Across the state, the outdoor planting window starts as early as Feb 24 in Washington and as late as Mar 12 in Chevy Chase.

Method Start indoors, then transplant
Days to maturity 90–120 days

Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings.

Onions Planting Dates by City

CityStart indoorsTransplant
WashingtonJan 13 – Jan 27Feb 24 – Mar 10
Downtown DCJan 18 – Feb 1Mar 1 – Mar 15
Columbia HeightsJan 18 – Feb 1Mar 1 – Mar 15
Mount PleasantJan 29 – Feb 12Mar 12 – Mar 26
Central 14th Street / Spring RoadJan 18 – Feb 1Mar 1 – Mar 15
Northwest OneJan 18 – Feb 1Mar 1 – Mar 15
Foggy BottomJan 29 – Feb 12Mar 12 – Mar 26
Mount Vernon TriangleJan 18 – Feb 1Mar 1 – Mar 15
H Street NEJan 18 – Feb 1Mar 1 – Mar 15
Pleasant PlainsJan 18 – Feb 1Mar 1 – Mar 15
NoMaJan 18 – Feb 1Mar 1 – Mar 15
PetworthJan 18 – Feb 1Mar 1 – Mar 15
Capitol RiverfrontJan 13 – Jan 27Feb 24 – Mar 10
Park ViewJan 18 – Feb 1Mar 1 – Mar 15
Golden TriangleJan 13 – Jan 27Feb 24 – Mar 10
ShawJan 18 – Feb 1Mar 1 – Mar 15
BrightwoodJan 18 – Feb 1Mar 1 – Mar 15
Adams MorganJan 18 – Feb 1Mar 1 – Mar 15
Kennedy StreetJan 18 – Feb 1Mar 1 – Mar 15
Southwest WaterfrontJan 13 – Jan 27Feb 24 – Mar 10
Barracks RowJan 18 – Feb 1Mar 1 – Mar 15
Union MarketJan 18 – Feb 1Mar 1 – Mar 15
AnacostiaJan 13 – Jan 27Feb 24 – Mar 10
Colorado TriangleJan 29 – Feb 12Mar 12 – Mar 26
Brentwood VillageJan 18 – Feb 1Mar 1 – Mar 15
The WharfJan 13 – Jan 27Feb 24 – Mar 10
Central 14th Street / WMATA Northern Bus BarnJan 18 – Feb 1Mar 1 – Mar 15
Van NessJan 29 – Feb 12Mar 12 – Mar 26
Benning RoadJan 18 – Feb 1Mar 1 – Mar 15
HillcrestJan 18 – Feb 1Mar 1 – Mar 15

Showing the 30 most populous of 35 District of Columbia cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all District of Columbia cities.

Frequently Asked Questions

When should I plant onions in District of Columbia?

In a typical District of Columbia location, start seeds indoors Jan 18 – Feb 1, then transplant outdoors Mar 1 – Mar 15. Across the state, the outdoor planting window starts as early as Feb 24 in Washington and as late as Mar 12 in Chevy Chase.

When is the last frost in District of Columbia?

The average last spring frost in District of Columbia ranges from March 24 in Washington to April 9 in Chevy Chase, based on NOAA 1991–2020 climate normals.

How long do onions take to grow?

Onions typically take 90–120 days from planting to harvest. Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings.

Other Crops in District of Columbia

When to plant onions in other states

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