When to Start Seeds Indoors for May 1 Last Frost (12 Weeks)?
Starting seeds 12 weeks before a May 1 last frost means sowing indoors around February 4.
How to use this tool
- Enter your average last spring frost date.
- Enter the number of weeks before transplanting to start seeds indoors (from the seed packet).
- The calculator returns the date you should sow seeds indoors.
Short-season Zone 4 gardens benefit from long indoor head-starts — find your February sow date for a May 1 frost.
Frequently asked questions
- When should I start seeds indoors?
- Most vegetables should be started 6–10 weeks before your last frost date. Tomatoes and peppers need 8–10 weeks; broccoli and cabbage need 4–6 weeks. Always check the seed packet.
- How do I find my last frost date?
- Enter your zip code on the USDA Plant Hardiness Zone Map website or ask your local cooperative extension service for the average last frost date in your area.