How do I start seeds indoors?
Getting Started
Choose seeds that benefit from an early start, like tomatoes, peppers, and broccoli. Check your last frost date (available from local extension services) and count back 6–8 weeks for most vegetables. Use clean containers with drainage holes and a sterile seed-starting mix, not garden soil.
Sow seeds at the depth recommended on the packet, usually 2–3 times the seed's diameter. Water gently, then cover with a humidity dome or plastic wrap to retain moisture.
- Label containers with seed name and date.
- Keep soil temperature 65–75°F for most seeds.
- Provide 12–16 hours of light daily once sprouts appear.
- Water from below or mist to avoid disturbing seeds.
- Thin seedlings when they have two sets of true leaves.
Light and Hardening Off
A sunny window often isn't enough; seedlings get leggy. Use fluorescent or LED grow lights placed 2–4 inches above plants, raising them as plants grow. Keep lights on 12–16 hours a day.
Before transplanting outdoors, harden off seedlings over 7–10 days. Start with a few hours in shade, gradually increasing time and sun exposure. This prevents transplant shock.
Common mistakes
- Starting seeds too early, leading to leggy, root-bound plants.
- Using garden soil, which can compact and harbor diseases.
- Skipping hardening off and putting seedlings directly into full sun.