When to plant Watermelon in Zone 4b
In Zone 4b, Watermelon: start seeds indoors around Apr 12–Apr 26; transplant outdoors around May 24–May 31; direct sow outdoors around May 17–May 31. Expect to harvest around Aug 10–Aug 24.
| Step | When |
|---|---|
| Start seeds indoors | Apr 12 – Apr 26 |
| Transplant outdoors | May 24 – May 31 |
| Direct sow outdoors | May 17 – May 31 |
| Harvest | Aug 10 – Aug 24 |
| Harvest | Aug 17 – Aug 24 |
Tip: Needs heat and a long season. In short-summer zones, start indoors and use black plastic to warm the soil.
Zone 4b averages a last spring frost around May 10 and a first fall frost around Sep 22. These are zone averages — look up your ZIP for your exact area.
See the full Zone 4b calendar in the tool →