Originally I started out with tomato seeds, carefully looking after the small plants before planting them out in the open. Growth was really slow and eventually a killer slug began cutting them down. We’re talking 20 cm (8 inch) plants, but they’re no match for a grown killer slug. Then I got some plants from a local supermarket. Still growing slowly, if not standing still.
Now I’m experimenting with a polystyrene box for self-watering. The compost is in contact with the water all the time and sucking up water through the three tubes in the middle of the box. This will provide the roots with the correct amount of moisture at all times, as long as you don’t let the box run completely dry. With this system you can actually go on vacation without supplying water, and come back a week later without having any difference in growth. It’s fascinating to look at the compost in the middle of really hot day and noticing that it stays wet no matter how hot the sun is burning. Needless to say, the tomato plants are now exploding.