Starting Seeds Indoors: Supplies, Setup & Strong Seedlings

Indoor seed starting gives you a head start, wider variety, and stronger plants. The setup is simple; consistency is key.

Supplies Checklist

• Containers: cell packs, soil blocks, recycled cups (drainage holes added). Clean with 10% bleach solution.
• Medium: sterile seed-starting mix (not potting soil, not garden soil). Fine, moisture-retentive, pathogen-free.
• Light: 2–4 ft LED shop lights (4000–6500K) or T5 fluorescent, 2–4" above canopy, 14–16 hrs/day on timer.
• Heat: seedling heat mat (70–75°F) for germination. Remove after sprouting.
• Cover: humidity dome or plastic wrap until germination.
• Labels: variety, date. Pencil on plastic tags.

Process

1. Moisten mix. Fill cells. Sow at packet depth (generally 2× seed width).
2. Cover. Heat mat. Light on.
3. Daily: check moisture, vent dome. Remove dome at first sprout.
4. Water from bottom (capillary) or gentle mist. Fertilize at half-strength after true leaves.
5. Harden off 7–10 days before transplant: increasing outdoor exposure.

Why It Works

No pests, perfect conditions, earlier harvest, money saved vs. transplants. One 4-ft shelf starts 200+ plants.