Seed Starting Guide

Starting seeds indoors gives you a 4–8 week head start on the growing season. In Zone 8b, that means starting warm-season crops like tomatoes and peppers in February while the ground is still cold. Our database tracks sowing method for 68 plants.

Indoor vs. Direct Sow

Plants to Start Indoors

The Setup

• Containers: Use seed-starting trays with drainage holes. Cell packs or soil blocks.
• Soil: Use sterile seed-starting mix, not garden soil. Garden soil compacts and harbors pathogens.
• Light: 14–16 hours of light. Shop lights 2 inches above seedlings. South-facing windows only with supplemental light.
• Heat: Most seeds germinate at 65–75°F. Heat mats for peppers, tomatoes, eggplants (80°F).
• Water: Bottom-watering prevents damping off. Keep soil moist, not wet. Cover trays until germination.

Hardening Off

The single most important step. Seedlings grown indoors have thin cuticles — they'll sunburn if moved directly outside. Hardening off takes 7–10 days:

1. Day 1–2: 1 hour outside in shade, protected from wind
2. Day 3–4: 2–3 hours, morning sun only
3. Day 5–6: 4–5 hours, increasing direct sun
4. Day 7–8: All day outside, bring in at night if below 45°F
5. Day 9–10: Full sun, all day, overnight outside