Vegetables · tender perennial grown as an annual

Tomato from seed

Solanum lycopersicum · also searched as cherry tomato, heirloom tomato, determinate, indeterminate

Germination temperature: 65 to 85°F (18 to 29°C)
Minimum soil temperature: 50°F (10°C)
Sowing depth: ¼ in (6 mm)
Days to germinate: 6 to 14 days
Light: Cover the seed; darkness helps
Before sowing: Nothing needed
Start indoors: 6 to 8 weeks before planting out
Plant out: 1 to 2 weeks after the last frost
Spacing: 24 in (60 cm) when trellised

Your dates from your last frost Seed not coming up?

Sowing

Start indoors 6 to 8 weeks before you plan to plant out, in a warm spot. Sow into moist mix and cover lightly. Cherry, determinate and indeterminate types all start the same way; they differ only in how big the plant gets.

Care and transplanting

Give seedlings strong light straight after they emerge or they stretch. Pot up once into a deeper container and bury the stem to the first leaves. Harden off over a week before planting out once frost has passed.

Problems

Stretched, pale seedlings need more light. Yellow lower leaves usually mean cold, soggy mix or hunger; wilting seedlings with a pinched stem base have damping off (see the troubleshooter). Purple tinges often mean cold roots.

Saving seed

Ferment the seed from fully ripe fruit in its own juice for a few days, rinse, dry on a plate and store cool and dry. Open-pollinated and heirloom tomatoes come true; hybrids do not.