Tomato Caging, Staking and Pruning: Why and How
Staked and pruned tomato plants tend to produce fewer, but larger, healthier and earlier fruit. Without a lot of effort, you can have success such as this with your crop. There are many established methods, just find the one that works for you and your garden.
Determinate tomatoes are often called “bush tomatoes". Determinate varieties grow in a compact, tidy form and the branches terminate (stop growing) at the same distance from the stem, ending in flower buds, and in turn the fruit. They usually reach a height of around four feet. Determinate plants produce all their tomatoes at one time.
Indeterminate tomatoes are often called “vine tomatoes" because of their continuous growth and sprawling habit, sprouting new leaves at the branch tip. This type of plant produces tomatoes throughout the season. They don't stop until they are killed off by frost.
Due to their natural tidy growth habit, determinate plants are better suited to cages because they need only minimal support. Common cage sizes are 42 and 54 inches tall, and are constructed of thick galvanized wired shaped like an inverted cone. Newer options are available in wire coated in colourful plastic. While these add a bit of whimsy to the garden, they serve the same purpose as the traditional wire variety. Set cages two to three feet apart for “bush tomato" plants.
Because of their trailing habit, indeterminate plants can grow 6-8 feet tall, so keep that in mind when planning for their support. Traditional staking formats are a “teepee", a “box", or a single pole. With each style, the structure should be six feet high and constructed of sturdy 1x2 lumber for the main supports. Stakes should be set in the ground at least one foot for stability. In general, set plants two feet apart.
In each instance, the plants will have to be loosely tied to the supports. Use strips of cloth, old pantyhose, or commercially available clips or plant ties. The key word is “loosely", as the material should not cut into the vine or girdle the plant as it matures. Consider the “Figure 8" system of placing one loop around the stake and the other around the main stem of the plant.
Cage or stake as soon as you plant your tomatoes, before the roots start to establish themselves in the area you will be staking. Disturbing the soil near an established tomato plant can damage its root system and affect the productivity of the plant.
With determinate plants, the removal of suckers that develop at the point where the leaves join the stem is important as these suckers deplete the plant of its needed nutrients. Simple pruning such as this also opens up the plant for increased light and better air flow, reducing the chance for disease. Simply pinch these leaves off at the main stem when they are small. Also, remove all suckers from the ground to the first flower cluster.
With indeterminate cultivars, all suckers from the ground up to the second flower cluster should be removed, and throughout the plant like the determinate varieties.
Some gardeners will top off the indeterminate plant a month or so prior to the first frost in autumn. Removing the top four inches of the main stem will help slow down plant growth, and divert the nutrients to the development of the ripening fruits.