You need to stock up on seeds in advance. People with experience know that you shouldn't wait until spring, but it's time to solve the problem in January, otherwise you won't be able to find the right variety later.
In addition, there will then be a sale of not the freshest and perhaps even expired seeds, which will not always please with good germination.
Sellers offer seeds that have already been treated with fertilizers and growth stimulants and do not require any preparatory treatments before planting.
For seeds that have not been pre-treated, pre-sowing preparation should begin as early as March. A set of procedures should be carried out.
The seeds should be laid out on a damp cloth, wrapped and placed in a plastic bag.
The seed material should remain in this condition and in a warm place for 2-3 days.
Then you need to spread the already swollen seeds into the prepared soil and sprinkle them with earth.
Next, you need to use standard methods of caring for tomato seedlings.