Mid-March is the sweet spot for Zone 6 tomato seeds.

Yes, aim for around March 15. That gives you the standard 6–8 weeks before your last frost date (typically early May in Zone 6). Any earlier and you’ll have leggy, root-bound plants begging to get outside. Any later and you’re waiting until July for fruit.

Starting is straightforward: a seed-starting mix, a sunny windowsill or grow light, and a little patience. Don’t overthink it. Tomatoes aren’t fussy seedlings—they just hate cold feet. Keep the soil warm (70°F) until they sprout, then back off a bit.

A common mistake is rushing them outside after the last frost. Soil temperature matters more than the calendar. Wait until the ground is consistently above 60°F—usually two weeks after your frost date—or you’ll stunt them.

Put your seed-starting date on the calendar and stick to it. Future You will thank Past You when you’re eating August tomatoes.