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When to Plant Watermelon in California

Watermelon is a sprawling vine crop that produces sweet, juicy fruits in hot weather. Varieties range from personal-sized icebox types to 50-pound giants.

California spans USDA hardiness zones 10a, 10b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.

Find Your County

Click your county for exact Watermelon planting dates based on your local frost dates.

Watermelon Planting Calendar for California

Zone 10a ~364 day growing season · Full guide →

Last frost: January 1 · First frost: December 31 · 364 day season

Activity When Date Range
Start Indoors December 4 Dec 4 – Dec 18
Transplant Outdoors January 8 Jan 8 – Jan 22
Direct Sow January 1 Jan 1 – Jan 22
Harvest March 19 Mar 19 – May 7
Zone 10b ~364 day growing season · Full guide →

Last frost: January 1 · First frost: December 31 · 364 day season

Activity When Date Range
Start Indoors December 4 Dec 4 – Dec 18
Transplant Outdoors January 8 Jan 8 – Jan 22
Direct Sow January 1 Jan 1 – Jan 22
Harvest March 19 Mar 19 – May 7
Zone 5a ~166 day growing season · Full guide →

Last frost: April 25 · First frost: October 8 · 166 day season

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors May 9 May 9 – May 23
Direct Sow May 2 May 2 – May 23
Harvest July 18 Jul 18 – Sep 5
Zone 5b ~178 day growing season · Full guide →

Last frost: April 18 · First frost: October 13 · 178 day season

Activity When Date Range
Start Indoors March 14 Mar 14 – Mar 28
Transplant Outdoors May 2 May 2 – May 16
Direct Sow April 25 Apr 25 – May 16
Harvest July 11 Jul 11 – Aug 29
Zone 6a ~193 day growing season · Full guide →

Last frost: April 10 · First frost: October 20 · 193 day season

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 17 Apr 17 – May 8
Harvest July 3 Jul 3 – Aug 21
Zone 6b ~205 day growing season · Full guide →

Last frost: April 3 · First frost: October 25 · 205 day season

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 10 Apr 10 – May 1
Harvest June 26 Jun 26 – Aug 14
Zone 7a ~221 day growing season · Full guide →

Last frost: March 25 · First frost: November 1 · 221 day season

Activity When Date Range
Start Indoors February 25 Feb 25 – Mar 11
Transplant Outdoors April 8 Apr 8 – Apr 22
Direct Sow April 1 Apr 1 – Apr 22
Harvest June 17 Jun 17 – Aug 5
Zone 7b ~235 day growing season · Full guide →

Last frost: March 18 · First frost: November 8 · 235 day season

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors April 1 Apr 1 – Apr 15
Direct Sow March 25 Mar 25 – Apr 15
Harvest June 10 Jun 10 – Jul 29
Zone 8a ~255 day growing season · Full guide →

Last frost: March 8 · First frost: November 18 · 255 day season

Activity When Date Range
Start Indoors February 8 Feb 8 – Feb 22
Transplant Outdoors March 22 Mar 22 – Apr 5
Direct Sow March 15 Mar 15 – Apr 5
Harvest May 31 May 31 – Jul 19
Zone 8b ~276 day growing season · Full guide →

Last frost: February 25 · First frost: November 28 · 276 day season

Activity When Date Range
Start Indoors January 28 Jan 28 – Feb 11
Transplant Outdoors March 11 Mar 11 – Mar 25
Direct Sow March 4 Mar 4 – Mar 25
Harvest May 20 May 20 – Jul 8
Zone 9a ~303 day growing season · Full guide →

Last frost: February 10 · First frost: December 10 · 303 day season

Activity When Date Range
Start Indoors January 13 Jan 13 – Jan 27
Transplant Outdoors February 17 Feb 17 – Mar 3
Direct Sow February 10 Feb 10 – Mar 3
Harvest April 28 Apr 28 – Jun 16
Zone 9b ~329 day growing season · Full guide →

Last frost: January 25 · First frost: December 20 · 329 day season

Activity When Date Range
Start Indoors December 28 Dec 28 – Jan 11
Transplant Outdoors February 1 Feb 1 – Feb 15
Direct Sow January 25 Jan 25 – Feb 15
Harvest April 12 Apr 12 – May 31

Growing Tips for California

Start seeds indoors 3-4 weeks early or direct sow after soil is warm. Plant on mounds with plenty of space. Check ripeness by looking for a yellow ground spot and dull thump when tapped.

Frequently Asked Questions

When should I plant Watermelon in California?

Planting dates for Watermelon in California depend on your USDA zone. California spans zones 10a, 10b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is California for planting?

California contains USDA hardiness zones 10a, 10b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Last updated: April 2026.