Planting Calendar Calculator
Almost every seed-starting failure is a calendar problem, not a soil problem. Pick your USDA zone â or enter your own last frost date â and get indoor start and outdoor planting dates for 10 common vegetables.
When should you plant?
Zone frost dates are regional averages (midpoints of published ranges). For dates pinned to your town, look up your ZIP at the Old Farmer's Almanac and enter them above â they override the zone average.
How the timing math works
Every planting window is counted backward or forward from your last spring frost. Cool-season crops go out before it; warm-season crops go out after it. The offsets below are the ranges that extension services and the Old Farmer's Almanac agree on:
| Vegetable | Indoor start | Outdoor action |
|---|---|---|
| Tomato | 6â8 weeks before transplant | Transplant 1â2 weeks after last frost |
| Pepper | 8â10 weeks before transplant | Transplant 2 weeks after last frost |
| Lettuce | â | Direct sow 2â4 weeks before last frost |
| Carrot | â (doesn't transplant) | Direct sow 2â4 weeks before last frost |
| Beans | â (doesn't transplant) | Direct sow at / 1 week after last frost |
| Cucumber | 2â3 weeks before transplant (optional) | Direct sow 1â2 weeks after last frost |
| Kale | 4â6 weeks before transplant | Transplant 2â4 weeks before last frost |
| Broccoli | 4â6 weeks before transplant | Transplant 2â4 weeks before last frost |
| Onion (from seed) | 8â10 weeks before transplant | Transplant 4â6 weeks before last frost |
| Peas | â (direct sow only) | Direct sow 4â6 weeks before last frost |
Worked example: Zone 6
Zone 6's average last frost is about April 11. Counting from there:
- Tomatoes: transplant ~April 22 (1.5 weeks after) â start seeds indoors ~early March (7 weeks earlier).
- Peppers: transplant ~April 25 (2 weeks after) â start indoors ~late February (9 weeks earlier).
- Peas & lettuce: direct sow mid-to-late March, as soon as soil can be worked.
- Beans: wait until ~April 15, when soil is reliably above 60°F â sown earlier, they rot.
Adjust for your microclimate
Zone averages smooth over real differences: a south-facing slope, a city heat island, or a nearby lake can shift your dates by two weeks either way. Treat the calculator's dates as your starting plan, then fine-tune with a soil thermometer â most warm-season seeds want soil above 60°F, peppers and cucumbers above 65°F â and keep row cover handy for surprise late frosts.
Understand the whole system
Frost dates, succession planting and fall gardens explained step by step.
Frequently asked questions
What is a frost date?
The average date of the last spring frost (or first fall frost) â the date with a 50% chance of no further frost. Zone values are regional averages; your town's exact dates come from local weather history.
How do I find my exact last frost date?
Use the Old Farmer's Almanac frost-date lookup by ZIP code, your state cooperative extension, or NOAA data. Zone averages are a solid fallback.
Should I plant exactly on the last frost date?
Only hardy crops. Tender crops like tomatoes and peppers go out 1â2 weeks after, once soil tops 60°F. Hardy crops like peas and kale go out weeks before.
What if a late frost is forecast after I planted?
Cover tender plants with row cover, frost cloth, buckets or jugs overnight; water the soil first (moist soil holds heat). Uncover in the morning.
Can I use this calendar for fall planting?
Yes â count backward from your first fall frost: subtract the crop's days to maturity plus ~2 weeks for slower fall growth.