When to plant Watermelon in Zone 1a
In Zone 1a, Watermelon: start seeds indoors around May 18–Jun 1; transplant outdoors around Jun 29–Jul 6; direct sow outdoors around Jun 22–Jul 6. Expect to harvest around Sep 15–Sep 29.
| Step | When |
|---|---|
| Start seeds indoors | May 18 – Jun 1 |
| Transplant outdoors | Jun 29 – Jul 6 |
| Direct sow outdoors | Jun 22 – Jul 6 |
| Harvest | Sep 15 – Sep 29 |
| Harvest | Sep 22 – Sep 29 |
Tip: Needs heat and a long season. In short-summer zones, start indoors and use black plastic to warm the soil.
Zone 1a averages a last spring frost around Jun 15 and a first fall frost around Aug 15. These are zone averages — look up your ZIP for your exact area.
See the full Zone 1a calendar in the tool →