When to plant Tomato in Zone 4a
In Zone 4a, Tomato: start seeds indoors around Mar 27–Apr 10; transplant outdoors around May 22–May 29. Expect to harvest around Aug 5–Aug 12.
| Step | When |
|---|---|
| Start seeds indoors | Mar 27 – Apr 10 |
| Transplant outdoors | May 22 – May 29 |
| Harvest | Aug 5 – Aug 12 |
Tip: Start indoors 6 weeks before last frost. Don't transplant until nights stay above 50°F (10°C).
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 →