How we worked it out
Updated as you change the numbers.
- Start indoors = last frost − weeks for the crop. Plant out = last frost ± weeks (cool crops go out before the last frost, warm ones after).
Method and assumptions
The timings are typical extension-service guidance: warm-season crops like tomatoes and peppers go out after the last frost, cool-season crops like broccoli and peas weeks before. Frost dates are averages, so there is a real chance of frost after them: watch the forecast.
Questions
When should I start tomato seeds indoors?
About 6 to 8 weeks before your last frost; plant out a week or two after it.
Sources
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.