The answer of course is to read the instructions on the seed packets and wait. When it says start four weeks before my last frost (24th of May, more or less) it means I shouldn’t start them until the 24th of April — two whole months away. Here are a few tips and reminders.
Anything that can hold a couple of inches of soil and has drainage holes in the bottom will do. For individual containers, use coffee cups — plastic or Styrofoam are fine, and yogurt cups are great too
All containers will need a plastic cover to keep up the humidity level.
However, the cover should not be totally airtight and is best removed as soon
as germination occurs. If you can match a plastic cake cover up with a pot the
same size you’ll have the perfect propagation chambers, or you can slip a large one over a number of
individual pots. Plastic stretch-wrap over the pots will also do the
trick, but poke a couple of holes in it. Clear plastic produce containers work well.
Once the seedlings begin to grow well, some liquid fertilizer will be
necessary, especially with the soil-free mixes, but check the instructions and
use at half strength or less. Too strong and there’s a chance the little guys will be
It’s essential for plant growth, but not for starting all seeds. The seeds of calendula, gazania, delphinium, pansy, verbena, and vinca are typical of those that prefer to be left in the dark until they germinate, but check daily because they will need light as soon as they do pop up. A simple LED grow light fixture suspended about 100cm or so above the seed trays is a perfect light source. Use a timer so that the lights are on for around fourteen hours each day. If you intend growing a large number of seedlings, use a small fan to provide gentle air circulation.
Don’t forget to move seed trays away from windows in the evening as it will get too cold there. Correct temperature is very important for seed germination. Most seeds, but not all, germinate best at a steady temperature of around 20 - 24C. After germination, the temperature lower.
Keep the growing medium for seeds and seedlings moist but not wet. Watering from the bottom up will cut down the risk of damping off disease. Use room temperature water and check at least once daily, because seeds will not germinate if the soil is allowed to dry completely.
There’s lots more to starting seeds, but if you follow these basic instructions
you’ll be successful, maybe even too successful. Now, what you should do is
clip and save this article until it’s the correct time to start seeds — unless
you can’t wait. But just remember, the house can get pretty steamy when it’s
brimming with enough tomato plants to attract Campbell’s attention.