Grow From Seeds

How to grow plants from seed, step by step

Growing from seed is a short chain of simple jobs. Do them in order and most of the problems never start.

The steps

  1. Read the packet. It tells you when to sow, how deep, and what temperature the seed likes. Check the use-by date too: old seed germinates less reliably (RHS).
  2. Fill a clean container with seed-starting mix and firm it to about 1cm (half an inch) below the rim. See containers and seed-starting mixes.
  3. Sow thinly and cover lightly. Cover with sieved compost, usually no more than the depth of the seed itself (RHS). The depth guide has a calculator.
  4. Water gently, then cover with a clear lid or glass to hold moisture, and keep it warm. Most seeds need around 18°C (65°F) to germinate (RHS). More in temperature.
  5. Uncover as soon as seedlings appear and move them to a bright place. A windowsill is often not enough; see light.
  6. Thin or prick out when they are big enough to handle, so they are not crowded. Crowding invites damping off.
  7. Start feeding at the first true leaves, every other watering, with a diluted liquid feed (Clemson). See fertilising.
  8. Harden off for two to three weeks before planting out (RHS). See hardening off.
  9. Plant out after the last frost for tender crops. The sowing planner works the dates back from your last frost.

When something goes wrong

Nothing came up? Use the germination troubleshooter. Seedlings that look wrong? Use the seedling problem picker. For a list of the usual slips, see the common mistakes.