Because tomato plants need lots of time before the first tomatoes are ripe, it is wise to start sowing in early spring. The precise moment to start sowing the seeds depends on whether you are growing the plants outdoors or in a greenhouse.

If you are going to grow in a greenhouse, you can start to sow the seeds from mid-February onwards. The young tomato plants can then be planted out in a greenhouse at the beginning of April. It’s a bit of a risk, because there is still a chance of night frost.

Every year I sow several tomato varieties in a greenhouse near my home. I always sow the seeds in mid-February and so far this has always gone well. Sometimes the plants suffer from the cold, which makes the lower leaves turn yellow, but as soon as the temperature goes up and the plant starts to grow, you won’t see that any more.

If you are going to grow the tomato plants outside, you can sow the seeds indoors from mid to end March. The plants can be planted outside in May. In the Netherlands, usually there is no frost after May 14th (Ice Saint’s day) and you can officially transplant the tomatoes outside. In recent years, the country has not been so coldso you can plant out the tomatoes earlier. If night frost is predicted and your tomato are already in the ground, cover them with fleece (or another cloth) for the night.

There are several different ways to sow tomatoes. Sowing in vermiculite works well and gives a high seed turnout.

Fill a container with 2 cm vermiculite (this can also be a fine sowing soil, but germination is often not so good) and sow the tomato seeds. Do not sow too densely, keep a space of 1 cm between seeds. Sprinkle the tomato seeds with 0.5 cm vermiculite and finish off with a good spray of water.

Cover the trays with a transparent lid or cling film (plastic wrap) with a few holes in it so that air can get in. Place the container with seeds in a warm place. Anything up to 20 degrees is fine.

After 5–7 days at 20 degrees the seeds will begin to germinate. As soon as the first havesprouted, the tray can go to a light (not in direct sun) and cool spot (between 15 and 18 degrees).

Once the leaves have unfolded in 50% of the sprouted plants, you can remove the cling film. Keep the vermiculite moist every day, because now that the plastic wrap is gone there will be more evaporation. Feeding plant food once a week with a plant spray is recommended, because vermiculite contains hardly any nutrients.

Once the young tomato plants are 2 to 3 cm tall they will start crowding each other in the tray.Now it is time to transplant them.Usea pot that is least a 12 cm wide at the top. Fill it with potting soil. Stirring with a stick or a knife, loosen the vermiculite and carefully pull out the tomato plant that you want to repot.Use your finger to poke a hole in the potting soil and carefully place the seedling into it.Press lightly around the stem, add a label and water everything well. Keep the plants in that light and cool room.

As the vines grow, it is wise to bind them to a stake so that theywill not fall over.When they are 20 to 25 cm tall and the weather forecast is good, you can transfer the plants to their final spot in the garden or greenhouse.

In the nursery we sow in trays of 104 soil plugs. The soil is firm yet airy. The seed is inserted in the plugs by a mechanical needle seeder. Someone checks if each plug has a seed in it and then the tray is scattered with vermiculite, watered, covered with plastic, and set in a warm greenhouse.

After 5 days the first seeds germinate and the plasticcovering is removed.When the seedlings are 1.5 cm tall they go to a somewhat cooler section where they stay for 5 to 9 weeks. Then the young tomato plants will be big enough for transplanting in to pots.