Growing Tomatoes: Determinate or Indeterminate

When choosing tomatoes to grow in your home garden, fruit size, flavor and days to maturity are obvious considerations, but they shouldn't be the only consideration. Tomatoes are classified according their growing habits. Determinate tomatoes grow to a predetermined height (typically 1 ½ to 2 feet) and cease growing while indeterminate tomatoes continue to grow throughout the growing season reaching heights of 6 feet or more. Which type you plant in your garden determines whether staking and pruning is required and affects fruit production and harvest as well.

Determinate Tomatoes

Determinate tomatoes are an excellent choice for raised beds and containers and may be labeled as patio tomatoes. They require minimal staking and pruning and requires less space that indeterminate varieties. Determinate plants bloom, set fruit and ripen all at one time making harvest quick and easy in late summer or early fall, but produce fewer fruit than indeterminate varieties. Pruning consists of occasional pinching to maintain overall shape. Aggressive pruning may remove buds and inhibit blooms and fruit. Many grow determinate tomatoes for canning as harvesting is quick and easy and many plants can be grown in a relatively small space.

Indeterminate Tomatoes

Indeterminate tomatoes require staking or caging to support the massive plant and to hold fruit above the ground. Suckers that grow in the notch between the main stem and side branches must be pinched out to prevent the growth of multiple stems that produce blooms and set fruit. Although some gardeners prefer to allow all suckers to grow and set fruit, this creates a large sprawling plant that is difficult to care for.

Indeterminate tomatoes bloom and set fruit up until frost. Removing blooms after the first week of August forces the plant's resources to the existing fruit. Tomatoes ripen gradually over several weeks in northern gardens and may extend to two to three months in southern regions, providing fresh plump fruit over an extended period. If allowed to set fruit late in the season, green tomatoes can be picked when frost threatens and ripened in a cool dark place. Wrapping tomatoes in newspaper and placing in a drawer or box hastens ripening.

Deciding whether to grow determinate or indeterminate tomatoes is an important decision. If time and space are limited, determinate varieties allow you to grow fresh tomatoes in a small space with little effort. For the more adventurous gardener who doesn't mind the additional time and work required, indeterminate tomato plants are an excellent choice as they provide an abundant supply of delicious vine-ripe tomatoes up until frost.

For more information on growing tomatoes see my other articles in this series.

Growing Tomatoes: Seed Starting
Growing Tomatoes: Caring for Tomato Seedlings
Growing Tomatoes: Preparing the Soil
Growing Tomatoes: Hardening Off Tomato Plants

Sources:

University of Illinois Extension: Tomato

Ohio State University Extension: Growing Tomatoes in the Home Garden

Iowa State University Extension: Tomatoes