FrostCal

When to Plant Watermelon in Arizona

In a typical Arizona location, start seeds indoors Jan 16 – Jan 23, then transplant outdoors Feb 27 – Mar 6. Across the state, the outdoor planting window starts as early as Jan 18 in Bullhead City and as late as Jun 18 in Flagstaff. 3 cities in Arizona are essentially frost-free and can plant on a year-round schedule.

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
PhoenixDec 8 – Dec 15Jan 19 – Jan 26
TucsonDec 23 – Dec 30Feb 3 – Feb 10
MesaJan 16 – Jan 23Feb 27 – Mar 6
ChandlerJan 16 – Jan 23Feb 27 – Mar 6
GilbertJan 16 – Jan 23Feb 27 – Mar 6
GlendaleDec 23 – Dec 30Feb 3 – Feb 10
ScottsdaleJan 16 – Jan 23Feb 27 – Mar 6
PeoriaDec 23 – Dec 30Feb 3 – Feb 10
TempeJan 16 – Jan 23Feb 27 – Mar 6
Tempe JunctionJan 16 – Jan 23Feb 27 – Mar 6
SurpriseDec 23 – Dec 30Feb 3 – Feb 10
YumaDec 11 – Dec 18Jan 22 – Jan 29
San Tan ValleyJan 4 – Jan 11Feb 15 – Feb 22
AvondaleDec 10 – Dec 17Jan 21 – Jan 28
GoodyearDec 10 – Dec 17Jan 21 – Jan 28
FlagstaffMay 7 – May 14Jun 18 – Jun 25
Casas AdobesJan 29 – Feb 5Mar 12 – Mar 19
Lake Havasu CityDec 8 – Dec 15Jan 19 – Jan 26
Casa GrandeJan 8 – Jan 15Feb 19 – Feb 26
BuckeyeDec 10 – Dec 17Jan 21 – Jan 28
Catalina FoothillsJan 23 – Jan 30Mar 6 – Mar 13
MaricopaJan 26 – Feb 2Mar 9 – Mar 16
Oro ValleyMar 5 – Mar 12Apr 16 – Apr 23
Sierra VistaMar 8 – Mar 15Apr 19 – Apr 26
Prescott ValleyMar 23 – Mar 30May 4 – May 11
PrescottApr 2 – Apr 9May 14 – May 21
MaranaJan 26 – Feb 2Mar 9 – Mar 16
Bullhead CityDec 7 – Dec 14Jan 18 – Jan 25
Apache JunctionJan 14 – Jan 21Feb 25 – Mar 4
Sun CityDec 23 – Dec 30Feb 3 – Feb 10

Showing the 30 most populous of 72 Arizona cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all Arizona cities.

Frequently Asked Questions

When should I plant watermelon in Arizona?

In a typical Arizona location, start seeds indoors Jan 16 – Jan 23, then transplant outdoors Feb 27 – Mar 6. Across the state, the outdoor planting window starts as early as Jan 18 in Bullhead City and as late as Jun 18 in Flagstaff. 3 cities in Arizona are essentially frost-free and can plant on a year-round schedule.

When is the last frost in Arizona?

The average last spring frost in Arizona ranges from January 4 in Bullhead City to June 4 in Flagstaff, 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 Arizona

When to plant watermelon in other states

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