Vegetable garden
Enter the average last spring frost date reported for your location to estimate when to start seeds indoors and sow or transplant outside.
No dates calculated yet.
| Crop | Start seeds indoors | Sow / transplant outside |
|---|---|---|
| Enter your local average last spring frost date to calculate this calendar. | ||
Every crop has a built-in planning rule in weeks relative to the local average last spring frost date you enter. For example, the tomato rule starts seeds indoors six weeks before that date and transplants one week after it. The calculator applies those offsets without estimating your local frost date.
USDA's Plant Hardiness Zone Map is based on average annual extreme minimum winter temperature and is designed as a general guide for perennial cold hardiness. It does not define spring frost dates, and local frost pockets and other microclimates can occur within a mapped zone.
Fact-check source: USDA Plant Hardiness Zone Map — How to Use the Maps.
Hardiness zones summarize extreme winter cold, not local spring frost timing. Use a local average last spring frost date from an Extension office or weather station instead.
Frost can damage tomatoes, peppers, and basil. Check the current forecast after calculating and wait for suitable soil and overnight temperatures.
Sowing indoors too far ahead can produce leggy, root-bound seedlings. Treat the calculated date as a planning point and compare it with the variety's seed packet.
The local date you enter is still an average, not the date of the final frost in every year. Recheck the forecast before setting out tender plants.
Get the average last spring frost date for your location from a local Extension office or nearby long-running weather station, then enter its month and day above. The calculator applies each crop's before-or-after-frost timing offset to that date.
No. USDA says plant hardiness zones describe average annual extreme minimum winter temperature and help compare perennial cold hardiness. A zone does not supply a location's average last spring frost date, so this calculator does not convert zones into frost dates.
Ask your local Extension office or consult records from a nearby long-running weather station. The calculator intentionally waits for that local month and day rather than guessing from a hardiness zone.
The built-in planning rules start heat-loving transplant crops such as tomatoes, peppers, and eggplant several weeks before the local average last spring frost date you enter. Check the seed packet for variety-specific timing.
No. An average frost date is not a forecast, and an actual frost can happen before or after it. Microclimate, current weather, soil temperature, and crop variety also matter, so check the forecast and seed packet before planting.
Protection may change your practical timing, but its effect depends on the crop, equipment, and weather. Tender crops can still be damaged by frost, so monitor the forecast and follow crop-specific guidance.
Planning guide only. Results use the local average last spring frost date you enter and do not predict this year's final frost. Check current conditions and variety-specific instructions before planting.
