Work out when to start seeds indoors by counting back from your last expected frost date.
100% Local
How to Use the Seed Starting Date Calculator
Enter the average last frost date for your area, choose a plant, then press Calculate. The tool counts backwards using that plant's typical indoor lead time and shows the window in which to sow seeds indoors. Use Clear to reset the form.
What the result means
The window is a range, because lead times vary between varieties and growing conditions.
Frost-sensitive crops get a longer lead time so they are ready to transplant after the last frost.
Some crops can also be sown directly outdoors after the last frost — the result says so when that applies.
These lead times are general planning values, not a guarantee for a specific variety or region.
Features
Covers 29 common vegetables, herbs and flowers started from seed
Counts back from your own last frost date instead of a fixed calendar
Flags crops that can be direct-sown after the frost
Works on desktop, tablet and mobile with no sign-up
All processing runs locally in your browser. Your data is not uploaded to any server.