How to Start Seeds Indoors: A Step‑by‑Step Guide

Get a head start on the growing season by sowing seeds indoors. Many houseplants and garden vegetables can be grown from seed, and nurseries now offer a wider selection than ever.

Essential Supplies

• Containers – Shallow trays, peat pots, or expanding pellets work well. Peat pots simplify transplanting.
• Seed‑starting mix – A sterile, fine‑textured medium designed for germination.
• Quality seeds – Fresh, viable seeds; some may need scarification or pre‑soaking.
• Plastic cover – A dome or plastic wrap to maintain humidity.
• Warmth & light – A bright spot (out of direct sun) or grow lights; a heat mat keeps soil at optimal temperature.

Choosing a Growing Location

A sunny window works, but artificial lights produce stronger, stockier seedlings. If space is limited, multi‑tier shelving with fluorescent lights above each level maximizes capacity.

Preparing Seeds & Medium

Seed Preparation

Most seeds sow directly from the packet. Hard‑coated seeds benefit from:

• Scarification: Gently nick the coat with a knife.
• Soaking: Submerge in warm water for 24 hours.

Moistening the Medium

Mix 4 parts seed‑starting mix with 1 part water in a bag; squeeze to blend. The medium should be damp, not soggy.

Step‑by‑Step Sowing

1. Fill clean containers with damp medium.
2. Sow seeds at a depth of 3× their diameter; do not compact.
3. Label each container with variety and date.
4. Cover with plastic dome or wrap. Water only when sprouts appear; avoid overwatering to prevent damping‑off.
5. Position grow lights 2 inches above the cover; run 16 hours on / 8 hours off.
6. When true leaves (second set) appear, thin to one strong seedling per cell.
7. Fertilize lightly after three true leaves develop; always water first to avoid burn.
8. Transplant when roots emerge from peat pots or pellets. For tray‑grown seedlings, wait until they’re robust.