Determinate and Indeterminate Tomatoes

When you buy tomato seeds or plants, they are classified as either determinate or indeterminate. I knew that determinate tomatoes tend to be better behaved than indeterminate and less likely to spread all over the garden, but I never really knew much more than that, so I looked it up.

Determinate tomatoes are also called “bush” tomatoes. These are varieties that are bred to grow to a compact height. When the fruit sets on the top or “terminal” bud, they stop growing, and all the fruit ripens at nearly the same time, then the plants die.

A prime example is the “Roma” tomatoes that I grow. I grow these plants closer together than the others as they are more compact. This year I staked each plant with a single stake rather than using cages as I did in the past.

It is recommended that determinate tomatoes not be pruned, as it will significantly reduce the yield.

These types make great “patio” tomatoes as they do well in containers. Celebrity and Rutgers are two other determinate varieties that I grow, although I was unaware that they were determinates.

Indeterminate varieties of tomatoes may also be called “vining” tomatoes. These types will grow, flower and set fruit throughout the growing season up until the first killing frost. They also tend to spread quite a bit and usually require cages for support. (And sometimes a heavy stake to support the cage if they get too top-heavy.)

Indeterminate tomatoes might benefit from pruning. One technique is to prune any flowers away about 1 month before the first killing frost to encourage the ripening of the remaining tomatoes.