Growing tomatoes is just as much fun as it is rewarding. We like to start tomatoes from seeds and watch the miracle of life to develop.
In this post we share how to start tomatoes from seeds using a ‘no fail method’ that involves less work. This method has worked for us for many years.
We grow tomatoes in soil in containers and in the open ground. We also grow tomatoes indoors hydroponically, read more about how to plant an hydroponic garden.
Where to get tomato seeds
We like to grow heirloom tomato varieties, they just seem to have so much more flavour. Since our weather conditions are very unique we like to buy the seeds locally because plants have to adjust to the climate they are in. We also make sure the plants need a short growing time (days to maturity), preferably less than 70 days. Read more about getting seeds for the new growing season and what Heirloom tomato varieties we grow in a northern garden.
When to start tomato seeds
The simple answer is: for most plants it’s written on the package when to start them. For early and mid season tomatoes it is 6 to 8 weeks before the last frost day (here is a link for Canada and USA last frost dates). If you have a greenhouse you can plant the tomatoes out about two weeks before the last frost day, so start them two weeks earlier. This is basically all you need to know.
However, if you have been confused over that question, see When to Start Tomatoes Indoors.
What pots and potting soil to use
For tomatoes (and peppers as well) I like the (free) one quart size yogurt containers, they have the optimal size for those plants. First I make some holes in the bottom for drainage, then fill them about half with potting soil (You will see later why just half full).
Seed starting mix or soil that is very fine and sterilized, might be important for some seeds that are very small and hard to start. For tomatoes, we simply use a potting soil mix.
When choosing a potting soil or a growing medium make sure to read the label. Some are really just growing mediums with no compost or fertilizer. It still is a good choice for seed starting, but as seedlings grow they do need some nutrients to grow. For refilling the pots, you can use some compost with the mix you have.
Make your own potting soil, Mel’s Mix from the Square Foot Garden book. Mix together:
1/3 peat moss
Plant the seeds
Here is a wordless video on how we start tomatoes from seeds. To watch the video on YouTube go here.
Make sure the soil for seed starting is moist. You do not want it to be dry nor really wet. Now plant 2-3 seeds into each container to make sure that at least one germinates. Covering the container with plastic also helps to keep the soil moist for better germination.
If more than one seed germinates, you can cut the little plants off and use them as cuttings. See also how to grow tomatoes from cuttings. It is a great method for those who have trouble to start tomatoes from seeds.
A sunny window or grow lights
For germination a seed needs moisture and warmth, not so much light. Find a nice warm spot in your house. Using a heat mat can be helpful too. I use the top of the washer and drier. As soon as the seeds are up, young plants need a lot of light.
If you have a sunny window to grow your seedlings at, that’s great. If not, you might need to add a grow light. There are many grow lights to choose from. We use 54W high output T5 fluorescent lights with a bulb life of 20,000 hours. This is a small investment for many years of healthy seedlings.
Labelling is important, so I know what varieties I am actually growing. I would never remember them all. It does not matter what kind of labels you use. Garden labels are great, but a plastic spoon works just as well. If I have many plants of the same kind, I just label the plastic containers.
Transplanting tomato seedlings
Tomatoes belong to the nightshade plant family along with eggplants, peppers, and potatoes. There is a unique thing about nightshade plants: they grow roots along the stem. This is important! In order to have a healthy, not leggy, tomato plant it is good to plant the seedling deep into the soil.
If I had started tomatoes in smaller containers, or bought seedlings from a greenhouse, I would transplant them into a bigger pot and bury as much as I can of the stem as soon as they are a little taller. Sometimes the plant is so leggy that the leaves only start at the top of the plant. This shows that the plant did not have enough light. Transplant it to a bigger pot anyway by burying the stem, give it more light, and it will start to get stronger and healthier.
You see, since my seedlings are already in a bigger container I save myself some work ;).
Once my little plants germinate and grow taller than the container, I gently cut off the lower leaves, and fill the pot with potting soil to the top. In a few more weeks they will be ready to go into the ground or their final container. Read all about transplanting tomatoes into the ground here.
I am sure there are more ways to start tomatoes from seeds. This way has worked for us. Share your method in a comment below.