Almost every seed packet, planting guide, and gardening app assumes you know two dates: your last spring frost and first fall frost. Here is the quick reference.
Approximate frost dates by zone
| Zone | Last spring frost | First fall frost | Frost-free days | |------|-------------------|-------------------|-----------------| | 3 | May 15 | Sep 15 | ~120 | | 4 | May 10 | Sep 25 | ~140 | | 5 | Apr 30 | Oct 5 | ~160 | | 6 | Apr 15 | Oct 15 | ~180 | | 7 | Apr 1 | Oct 30 | ~210 | | 8 | Mar 15 | Nov 15 | ~240 | | 9 | Feb 15 | Dec 1 | ~290 | | 10 | Jan 30 | Dec 15 | ~320 |
These are 50% probability dates — meaning half of years frost will occur after this date. Add 2 weeks of buffer for tender crops.
How to use frost dates
- 2 weeks before last frost: direct-sow peas, spinach, radishes
- At last frost: transplant lettuce, broccoli, cabbage starts
- 2 weeks after last frost: transplant tomatoes, peppers, basil; direct-sow beans, corn, squash
- 8–10 weeks before first frost: sow fall brassicas
- 2 weeks before first frost: pull tender crops, cover beds
Sapience Garden pulls your actual local frost dates from weather data, not table averages. See it in the Climate tab.