Seed Starting

March/April is the perfect time to start seeds inside. The materials that you’ll need are:

  • Growing media – peat moss, perlite, and fertilizer (note that fertilizer is optional at this stage)
  • Vermiculite to layer on top of the seeds (or use a dome) to reduce moisture evaporation
  • Appropriate tray inserts – I use 72-cell inserts unless I want to avoid potting up later
  • Fan for air flow
  • Watering can with sprayer
  • And, of course, the seeds themselves!

The key steps for seed starting include:

  1. Start with a soilless mixture – seed-starting mix is ideal as it’s sterile and won’t carry as much disease or insects
  2. Dampen your growing media (moist but not sopping wet) before you plant the seeds as watering afterward may alter seed depth
  3. Plant the seeds at a depth of about 2-4 times the width of the seed itself
  4. Cover seeds with soil and then add a layer of vermiculite (or a humidity dome) to maintain dampness in the soil
  5. If possible, aim for a soil temperature of 25oC by placing your seed trays in a warm place or on top of a horticultural (waterproof) heating pad
  6. Monitor dampness every day – ungerminated seeds should be constantly damp (again, not sopping wet) while germinated seeds need to be less damp on occasion in order to ensure that oxygen is not pushed out of the soil by water
  7. Finally, germinated seedlings should be placed in bright light and rotated regularly – as modern windows are designed to filter out most light energy, even a south-facing window may need to be supplemented with lamps.

For indeterminate vegetables, which produce a harvest over a long period of time (such as tomatoes and kale), you can start all seeds at the same time. However, for determinate vegetables where you harvest everything at once (such as cabbage and carrots), start these seeds in tranches 2 weeks apart for continued harvest later throughout the season, if desired.

We hope this info has inspired you to start to planting some seeds! As always, please feel free to reach out at if you have any questions about our Grow Veggies program or any of the topics in our newsletter!