When to plant Watermelon in Zone 4a
In Zone 4a, Watermelon: start seeds indoors around Apr 17–May 1; transplant outdoors around May 29–Jun 5; direct sow outdoors around May 22–Jun 5. Expect to harvest around Aug 15–Aug 29.
| Step | When |
|---|---|
| Start seeds indoors | Apr 17 – May 1 |
| Transplant outdoors | May 29 – Jun 5 |
| Direct sow outdoors | May 22 – Jun 5 |
| Harvest | Aug 15 – Aug 29 |
| Harvest | Aug 22 – Aug 29 |
Tip: Needs heat and a long season. In short-summer zones, start indoors and use black plastic to warm the soil.
Zone 4a averages a last spring frost around May 15 and a first fall frost around Sep 18. These are zone averages — look up your ZIP for your exact area.
See the full Zone 4a calendar in the tool →