GrowZone

Crop by USDA zone

When to plant watermelon in zone 9a

In USDA zone 9a, plant watermelon around Mar 15, after the representative last frost near Mar 1. Start seeds indoors around Feb 8.

This page summarizes the supported ZIPs in zone 9a. Your exact city can move earlier or later, so use the ZIP lookup for the frost-station-specific answer.

Get exact watermelon dates by ZIP code.

Seed starting schedule

Watermelon dates for Las Vegas, NV

StepDateHow to use it
Start IndoorsFebruary 8, 2026Start seeds under lights or in a bright indoor seed-starting space.
Transplant OutdoorsMarch 15, 2026Move hardened-off seedlings outside after the frost-risk window.
Direct SowMarch 15, 2026Sow seed outside when the crop and soil can handle the window.
Jacksonville, FL · Zone 9a Watermelon Mar 15 Open ZIP-specific answer · last frost Mar 1 San Antonio, TX · Zone 9a Watermelon Mar 15 Open ZIP-specific answer · last frost Mar 1 Las Vegas, NV · Zone 9a Watermelon Mar 15 Open ZIP-specific answer · last frost Mar 1 Portland, OR · Zone 9a Watermelon Apr 15 Open ZIP-specific answer · last frost Apr 1 Seattle, WA · Zone 9a Watermelon Apr 3 Open ZIP-specific answer · last frost Mar 20