FrostCal

When to Plant Watermelon in Washington

In a typical Washington location, start seeds indoors Feb 24 – Mar 3, then transplant outdoors Apr 7 – Apr 14. Across the state, the outdoor planting window starts as early as Mar 15 in Port Townsend and as late as Jun 13 in Cheney.

Method Start indoors, then transplant
Days to maturity 70–90 days

Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost.

Watermelon Planting Dates by City

CityStart indoorsTransplant
SeattleFeb 13 – Feb 20Mar 27 – Apr 3
Tri-CitiesMar 30 – Apr 6May 11 – May 18
SpokaneMar 29 – Apr 5May 10 – May 17
TacomaFeb 8 – Feb 15Mar 22 – Mar 29
VancouverMar 1 – Mar 8Apr 12 – Apr 19
BellevueFeb 8 – Feb 15Mar 22 – Mar 29
KentFeb 20 – Feb 27Apr 3 – Apr 10
EverettFeb 24 – Mar 3Apr 7 – Apr 14
RentonFeb 13 – Feb 20Mar 27 – Apr 3
Federal WayFeb 8 – Feb 15Mar 22 – Mar 29
Spokane ValleyMar 29 – Apr 5May 10 – May 17
YakimaApr 10 – Apr 17May 22 – May 29
KirklandFeb 8 – Feb 15Mar 22 – Mar 29
BellinghamMar 4 – Mar 11Apr 15 – Apr 22
KennewickFeb 28 – Mar 7Apr 11 – Apr 18
AuburnFeb 20 – Feb 27Apr 3 – Apr 10
PascoFeb 28 – Mar 7Apr 11 – Apr 18
MarysvilleFeb 24 – Mar 3Apr 7 – Apr 14
RedmondFeb 8 – Feb 15Mar 22 – Mar 29
LakewoodFeb 11 – Feb 18Mar 25 – Apr 1
OlympiaApr 1 – Apr 8May 13 – May 20
ShorelineFeb 8 – Feb 15Mar 22 – Mar 29
RichlandMar 9 – Mar 16Apr 20 – Apr 27
South HillMar 14 – Mar 21Apr 25 – May 2
SammamishFeb 8 – Feb 15Mar 22 – Mar 29
BurienFeb 2 – Feb 9Mar 16 – Mar 23
LaceyApr 1 – Apr 8May 13 – May 20
City of SammamishMar 2 – Mar 9Apr 13 – Apr 20
BothellFeb 8 – Feb 15Mar 22 – Mar 29
EdmondsFeb 9 – Feb 16Mar 23 – Mar 30

Showing the 30 most populous of 133 Washington cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Washington cities.

Frequently Asked Questions

When should I plant watermelon in Washington?

In a typical Washington location, start seeds indoors Feb 24 – Mar 3, then transplant outdoors Apr 7 – Apr 14. Across the state, the outdoor planting window starts as early as Mar 15 in Port Townsend and as late as Jun 13 in Cheney.

When is the last frost in Washington?

The average last spring frost in Washington ranges from March 1 in Port Townsend to May 30 in Cheney, based on NOAA 1991–2020 climate normals.

How long do watermelon take to grow?

Watermelon typically take 70–90 days from planting to harvest. Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost.

Other Crops in Washington

When to plant watermelon in other states

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