When to plant Watermelon in Zone 3b
In Zone 3b, Watermelon: start seeds indoors around Apr 22–May 6; transplant outdoors around Jun 3–Jun 10; direct sow outdoors around May 27–Jun 10. Expect to harvest around Aug 20–Sep 3.
| Step | When |
|---|---|
| Start seeds indoors | Apr 22 – May 6 |
| Transplant outdoors | Jun 3 – Jun 10 |
| Direct sow outdoors | May 27 – Jun 10 |
| Harvest | Aug 20 – Sep 3 |
| Harvest | Aug 27 – Sep 3 |
Tip: Needs heat and a long season. In short-summer zones, start indoors and use black plastic to warm the soil.
Zone 3b averages a last spring frost around May 20 and a first fall frost around Sep 12. These are zone averages — look up your ZIP for your exact area.
See the full Zone 3b calendar in the tool →