Determining tomatoes

Anne Swithinbank masterclass on understanding tomatoes

- Anne Swithinbank

Q I’m growing tomatoes for the first time this year. I sowed a few seeds and bought plants, but their behaviour and training is confusing me. What does determinate and indeterminate mean? Gemma Stanhope, Guildford, Surrey

A The habit of tomatoes varies from one variety to another. Those we refer to as determinate are the bushy types. They don’t have an obvious main stem, but branch naturally and sprawl. Low on maintenance, they need neither supporting or pinching out and are ideal for growing in containers. Bush tomatoes are good for windy sites where canes might topple, and plants fit easily under cloches where more cosseting is needed in colder regions. They are not so useful for greenhouse growing, because they take up sideways space.

Indeterminate or cordon types have an obvious main stem, although side stems can also grow long. These are usually trained on a single stem, tied into a cane or wound around a string secured above the plant. Their tall, narrow habit saves space. Side-shoots are removed to prevent a tangle and control the number, quality and ripening of fruit.