Winter is not over, but gardeners are already starting to plan their vegetable garden and some are eagerly waiting to start their seeds indoors.
Indoor sowing, for which vegetables?
The production time of a vegetable, between sowing and maturity, can vary depending on their category and their origin. It will take longer for a plant to produce a fruit, like a pepper, than a leaf like a lettuce. A plant like the tomato, which is native to Mexico, will require more hours of sunlight to produce its fruit than the pea, which is native to a temperate climate.
To produce a tomato, it takes around 100 days at 20°C to 25°C from sowing to harvest. Unfortunately for us, we do not have an average temperature of 23°C for 100 days in Quebec. It will therefore be necessary to extend this heat period by practicing indoor sowing. Some vegetables absolutely need indoor sowing and others need to be sown outdoors . And finally for some, we have the choice depending on whether we want vegetables earlier or not.
Here is a table that can help us sort it all out:
When to sow indoors?
The most common mistake when sowing indoors is to sow too early and end up with vegetables that are too large, wither and cannot be planted outside because it is too cold. Transferring and planting your indoor seedlings outdoors should be done after the last frost, depending on your region, and from the four-leaf stage, counting the cotyledons. So your vegetables need to be ready on time, but not too early.
It will be important to establish a planting schedule if you have several vegetables to sow. Count down from the last frost date, depending on your vegetables. You will generally find on your seed packets indications of the number of days or weeks to wait before planting. For example: you live in Laval (the last frost is around May 15) and the sowing instructions are 6 weeks before the last frost, your sowing date for this vegetable will therefore be around April 3. Allow a little less time if the room where you sow is well heated.
Equipment for indoor sowing
- The seeds. It's best not to buy them too far in advance.
- The potting soil or substrate. Do not use soil from your garden. Substrates sold for sowing in garden centers will be perfectly suitable, such as Fafard organic seedling soil or Promix seedling soil ;
- The containers can be trays, pots for grouped sowing or individual sowing (peat cups, peat pellets, tray in individual cells );
- The stickers . You must identify your seedlings. We prepared a kit of 12 labels with a Sharpie ;
- A bucket or large bowl;
- Transparent domes to cover seedling containers;
- A manual sprayer to keep your seedlings moist.
You can recycle various containers (milk carton bottoms, yogurt pot, etc.). However, it is important to wash them well with soap and make holes in the bottom to prevent water accumulation.
Sowing
Make your cake mix . Mix your dry potting soil with water in a bucket, mixing everything together. Add the water gradually, avoiding excess water. When you squeeze the mixture into your hand, a slight excess of water should flow between your fingers, but no more.
Prepare your labels. Write the name of each variety and the sowing date in advance with a permanent marker on your labels.
Fill the containers. Fill your containers with the mixture, packing it lightly. Level your mixture about 2 cm from the top edge. If you sow directly in individual containers, make a hole of recommended depth on the bag, place three seeds in the center of each container. For grouped sowing of small seeds in a tray, level out 2 cm from the edge. Open your bag, hold it horizontally above the substrate while moving gently from right to left to cover the surface of your tray as evenly as possible. Pack lightly with a wooden block then moisten with a spray bottle.
You can also sow seeds online. Draw lines with a pencil at the distance and depth recommended on the sachet. Place the seeds one by one in the furrow 1 cm apart, then cover the furrow with the substrate. Moisten using a spray bottle.
Plant an identified label in front of your seedlings.
Cover the seedlings. Germination requires constant humidity at the seed level, availability of air and a generally high temperature. It will therefore be important to cover your seedlings with plastic domes, windows or plastic film to maintain good humidity and avoid drying out, until the seeds germinate.
Seedling monitoring
Although seeds do not need light for germination, you can maintain artificial lighting (fluorescent lamp) 15 cm from your seedlings to maintain a constant temperature. If you place your seedlings on the edge of a window, avoid exposing them to direct sunlight so as not to have too significant temperature variations.
After germination, remove domes, plastic or glass, to avoid excess humidity and disease on your young seedlings. If you have the possibility, it is best to monitor your seedlings in a room that you frequent as little as possible so that you can lower or raise the temperature and humidity to better control the growth of your seedlings.
Light becomes very important after germination. You can use artificial lighting or place your seedlings on a window sill.
Monitoring watering is also tricky on your young seedlings. You can use an undrilled tray, put your seedling containers on this tray and pour about 2 cm of water into the tray. The containers will absorb water without damaging the young foliage as watering with a watering can would do.
You can find all the seeds and sowing equipment on our site and in our garden center.
We will publish a section on outdoor sowing in a few weeks. Until then, good luck with your indoor seedlings!
