Plan with supported city station records or your own local frost dates. Use the manual calendar, seed-starting planner, fall deadline calculator, succession scheduler and seed-tray calculator below.
2357 station locations available. Search a city or station name; not every town is represented. Outside coverage? Use your own frost dates.
Manual planting calendar
Use local frost dates from a source you trust. These are general planting windows, not weather forecasts.
Seed-starting & hardening planner
Work backward from transplanting using your variety’s instructions. Hardening is shown separately, not added twice.
Fall harvest deadline calculator
Subtract packet days to maturity and your chosen buffer from a frost date. Check whether the packet counts from sowing or transplanting.
Succession sowing planner
Fit repeated sowings before your harvest target. Harvest estimates depend on weather, variety and your assumptions.
Seed & tray quantity planner
Estimate one seed per cell using expected germination and seedling survival. The extra margin is optional; results vary.
These tools calculate from your inputs. Save or print with your browser. Check forecasts, soil conditions and seed-packet instructions before planting.
What each tool does
- Frost date lookup: shows average last spring and first fall frost for supported US towns, using NOAA climate normals from the nearest weather station.
- Seed-starting and hardening calculator: counts back from your transplant date to give a sowing window.
- Fall planting deadline calculator: counts back from your first fall frost to the latest date to plant.
- Succession planting planner: schedules repeat sowings so harvests are staggered.
- Seed and tray quantity calculator: estimates how many seeds and trays you need for a target number of plants.
Where the numbers come from
Frost dates are averages drawn from NOAA NCEI climate normals for 1991 to 2020. They describe past patterns and are not a forecast. Read Data Sources and Limitations for the full method and the Gardening and Data Disclaimer before relying on any result.
A simple planning order
- Find your average last spring frost and first fall frost.
- Decide your transplant date for tender crops.
- Use the seed-starting calculator to find when to sow indoors.
- Use the seed and tray calculator to work out how much seed to buy.
- Use the succession planner and fall deadline calculator for repeat and autumn crops.
Frost dates vary from yard to yard, so compare every result with your local forecast and your local extension office.