The first tomato plants are ready for those of you with glasshouses or conservatories. It is a good idea to leave the plants in their 9cm pots until you can see yellow on the first flowers. This encourages the plants to make flowers rather than leaves and will give you an earlier crop on a more compact plant. After potting on, start feeding when the first fruit is the size of a marble.
For the earliest crop, try the basket tomato Maskotka, which can be grown in a pot as well. It is usually at least three weeks ahead of the cordon varieties.