Part 1: Propagation by seed

6. Sowing

Basic seed sowing instructions.

  1. Fill your containers with compost and water until damp but not flooded.
  2. Follow the instructions on the seed packet! A lot of specialist knowledge, trials and research goes into those sowing instructions on the back of that packet. It is in the seed company’s interest for you to get a good germination rate, so they do give the best advice possible. Even commercially sourced wholesale seed comes with sowing instructions.
  3. Usually, it speeds up germination and reduces the seedlings drying out if you cover the container with a clear propagator lid to keep humidity high until germination has occurred.
A plant incubator with seedlings growing within, sitting on a windowsill to catch light.

Simon Speed via Wikimedia / CC0 1.0

Top tip from a commercial wholesale propagation nursery

If you want to be able to leave your seedlings in their containers for longer to give you a more flexible planting out/potting on date, then when you are filling the containers before sowing:

  • Fill to about 2cm deep with compost (just a thin layer to cover the holes in the bottom of the pots or trays).
  • Sprinkle a thin layer of slow-release fertiliser over the compost.
  • Fill the containers to the top with compost.

The seedlings then germinate in the compost without being affected by the fertiliser below (which could prevent germination), grow their roots down until they reach the fertiliser and can remain growing in that container for a whole season, if necessary, as the fertiliser provides the nutrients they require.

Activity

Seed sowing by hand is labour intensive and so often not viable for a commercial enterprise.

Search on YouTube for ‘seed sowing machines’ and watch how commercial nurseries speed up the process.