Tips for Sowing Tomatoes from Seed

Tools and materials for sowing Tomato seed -  © GAP Photos

Tools and materials for sowing Tomato seed -
© GAP Photos

If you are a fan of tomatoes, you may want to grow your own, and mid spring is the perfect time to start, although if you have a greenhouse you can sow even earlier. There are so many varieties of tomato available as seed, and it is fun to select a range to grow. There are a few things to remember when growing tomatoes from seed, so we thought we would give a few tips.

1. Sow the seeds finely

Woman sowing tomato seeds - © GAP Photos

Woman sowing tomato seeds – © GAP Photos

Seedlings grow stronger with less competition with other seedlings, so try and sow the seeds thinly. Use the crease in your palm and your index finger to control where the seeds land in the seed tray.

2. Don’t forget to label as you sow

Seed tray with lines of tomato seedlings -  © GAP Photos

Seed tray with lines of tomato seedlings – © GAP Photos

All tomato seedlings look the same, so if you are growing more than one variety, clearly label as you sow so you are able to identify the germinated seedlings.

3. Keep them warm

Woman putting tray of sown tomato seed into propagator in greenhouse -  © GAP Photos

Woman putting tray of sown tomato seed into propagator in greenhouse – © GAP Photos

Tomatoes do need warm and consistent soil temperatures to germinate – from 21 to 25C, so consider using a propagator. If you don’t have a propagator, you could tie a plastic bag over the top of the pot, or pop the sown seeds in a warm part of the house, such as their airing cupboard. and then bring out when the seeds have germinated.

4. Handle with care

Woman carefully potting on tomato seedlings - © GAP Photos

Woman carefully potting on tomato seedlings – © GAP Photos

The seedlings that appear are very delicate and easily damaged. When you transplant the seedlings, hold them by their cotyledons (first leaves) rather than the stem. As the plants will shed their cotyledons anyway, it does not matter if these get damaged during the transplantation process.

5. Introduce young plants to the garden gradually as the summer approaches

Close up of line of tomato seedlings - © GAP Photos

Close up of line of tomato seedlings – © GAP Photos

Young tomato plants are very tender, and will need hardening off outside before they are planted in their final locations. Harden them off gradually by leaving them outside during the day in mid to late spring, before moving them back inside during the night.