FrostCal

When to Plant Onions in Kansas

In a typical Kansas location, start seeds indoors Feb 2 – Feb 16, then transplant outdoors Mar 16 – Mar 30. Across the state, the outdoor planting window starts as early as Mar 7 in Kansas City and as late as Mar 31 in Garden City.

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
WichitaJan 31 – Feb 14Mar 14 – Mar 28
Overland ParkJan 30 – Feb 13Mar 13 – Mar 27
Kansas CityJan 24 – Feb 7Mar 7 – Mar 21
OlatheJan 30 – Feb 13Mar 13 – Mar 27
TopekaFeb 5 – Feb 19Mar 19 – Apr 2
LawrenceFeb 1 – Feb 15Mar 15 – Mar 29
ShawneeJan 24 – Feb 7Mar 7 – Mar 21
ManhattanFeb 5 – Feb 19Mar 19 – Apr 2
LenexaJan 30 – Feb 13Mar 13 – Mar 27
SalinaFeb 7 – Feb 21Mar 21 – Apr 4
HutchinsonFeb 7 – Feb 21Mar 21 – Apr 4
LeavenworthFeb 1 – Feb 15Mar 15 – Mar 29
LeawoodJan 30 – Feb 13Mar 13 – Mar 27
Dodge CityFeb 10 – Feb 24Mar 24 – Apr 7
Garden CityFeb 17 – Mar 3Mar 31 – Apr 14
EmporiaFeb 4 – Feb 18Mar 18 – Apr 1
Junction CityFeb 1 – Feb 15Mar 15 – Mar 29
DerbyFeb 3 – Feb 17Mar 17 – Mar 31
Prairie VillageJan 24 – Feb 7Mar 7 – Mar 21
HaysFeb 8 – Feb 22Mar 22 – Apr 5
GardnerFeb 2 – Feb 16Mar 16 – Mar 30
LiberalFeb 9 – Feb 23Mar 23 – Apr 6
PittsburgJan 27 – Feb 10Mar 10 – Mar 24
NewtonFeb 3 – Feb 17Mar 17 – Mar 31
Great BendFeb 13 – Feb 27Mar 27 – Apr 10
McPhersonFeb 7 – Feb 21Mar 21 – Apr 4
El DoradoFeb 2 – Feb 16Mar 16 – Mar 30
AndoverJan 30 – Feb 13Mar 13 – Mar 27
OttawaFeb 7 – Feb 21Mar 21 – Apr 4
WinfieldFeb 5 – Feb 19Mar 19 – Apr 2

Showing the 30 most populous of 40 Kansas cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Kansas cities.

Frequently Asked Questions

When should I plant onions in Kansas?

In a typical Kansas location, start seeds indoors Feb 2 – Feb 16, then transplant outdoors Mar 16 – Mar 30. Across the state, the outdoor planting window starts as early as Mar 7 in Kansas City and as late as Mar 31 in Garden City.

When is the last frost in Kansas?

The average last spring frost in Kansas ranges from April 4 in Kansas City to April 28 in Garden City, 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 Kansas

When to plant onions in other states

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