By Michelle Fabio
You can know everything there is to know about growing tomatoes, but if you don’t know *when* to start the seeds, all that knowledge is for naught.
So when should you start sowing tomato seeds?
First of all, keeping in mind that the soil for germinating tomato seeds needs to be at a constant 50Â°F (10Â°C) or higher, know that if you live in a colder climate, you’re going to have to start your seeds indoors and then move them outside–tomatoes don’t tolerate frost at all and most cooler spots just don’t have long enough summers for a full tomato growth season from sowing to harvest.
And so, the most important date to know in starting tomato seeds is the expected date of the last frost. You’ll want to put your plants outside about two to three weeks after the last frost date; you should sow your seeds about 6-8 weeks before their transplant date for best results.
You can find out some general estimates on the last frost for your area on The Old Farmer’s Almanac Frost Chart for the United States.