AMES — Tomatoes are one of the most popular vegetables grown at home. They are available in a variety of sizes, shapes and colors and benefit from staking and training to keep the sprawling plants off the ground. In this article, horticulturists with Iowa State University Extension and Outreach answer questions about the options for home gardeners to train and stake their tomatoes.
Why is staking tomatoes beneficial?
There are several advantages to staking and training tomato plants in the home garden. Tomato plants trained so they are growing off the ground often produce better quality fruit than those allowed to sprawl on the ground. This is, in part because foliar disease problems are generally less severe due to better air circulation. Training tomatoes also conserves valuable garden space for gardeners with small plots. Plus, trained tomatoes are easier to cultivate and harvest.
What type of tomatoes should be trained or staked?
Tomatoes can be divided into two major groups based on how they grow: determinate and indeterminate. Determinate tomatoes are smaller, more compact plants. They grow to a certain height, stop, then flower and set all their fruit within a short period of time. Indeterminate tomatoes continue to grow, flower, and set fruit until killed by frost in the fall. This growing habit makes indeterminate tomatoes large, sprawling plants.
Both types of tomatoes benefit from staking and training. Occasionally, you can grow determinate types with minimal support. Often for best fruit production, indeterminate types need to be trained or staked in some way.
When should I stake or start training tomato plants?
Tomatoes grow quickly after being planted in the spring. You should have the materials needed for whatever method of training you plan to use on-hand at the time of planting. Many gardeners will set up the equipment necessary for training at the time of planting. Early- to mid-June is when most tomato plants are large enough to start actively training and staking plants.
What methods can be used to stake a tomato plant?
Training methods vary, but the three most common methods for home gardeners are the wire cage, single stake and weave system.
Utilizing a wire cage is one of the most popular methods for training tomatoes because it requires less attention. This method works for both types of tomatoes but is ideal for determinate varieties. Manufactured cages are readily available at garden centers. They tend to be too small, especially for indeterminate varieties and can sometimes be unstable and easily topple. A tomato cage can be constructed by creating a cylinder from concrete reinforcing wire or similar material with a mesh large enough to allow the fruit to be harvested. For most tomato plants a wire cage 20 to 24 inches in diameter and 4 to 5 feet tall is ideal. Remove the horizontal wire at the bottom of the cage and stick the vertical wires or “feet” into the soil. Both manufactured and homemade cages can be further stabilized by attaching the cage to one or two stakes. When utilizing wire cages, space plants 2 to 3 feet apart. As the plant grows, simply ensure stems stay within the wire cage.
Training using a single stake requires placing one 7- to 8-foot-long stake 1 to 2 feet into the ground positioned 3 to 4 inches from the plant. As the tomato grows, tie the plant to the stake with stretch ties or strips of nylon hose or cloth about every 12 inches along the stem. Tie the material in a loose figure 8, with the stake in one loop and the stem in the other. When utilizing this method of pruning, pinch out the side shoots or suckers that form in the axils of the leaf and stem. Tomatoes that are staked can be planted 1.5 to 2 feet apart in rows spaced 4 to 5 feet apart. This training method works well with indeterminate tomato cultivars but is not recommended for determinate types.
If you grow a lot of tomato plants, the weave system works well. Plant tomatoes 18 to 24 inches apart within rows spaced 4 to 5 feet apart. Drive a 6- to 7-foot-long stake one foot into the ground every two plants along the row. Use a sturdy metal post 7- to 8-foot long driven 1 to 2 feet into the ground at each end of the row. When the plants are 12 to 14 inches tall, begin the weave at 8 to 10 inches off the ground. Tie twine to the end post and sweep the twine past the two plants along one side of the row. Then loop the twine around the first stake and pull it tight. Continue this process while pulling the twine tight as you go down the row keeping tension on the twine all the way down. At the end of the row, make a loop around the end post and turn around to repeat the process on the other side of the row, enclosing the plants between the two strings of twine. When you get back to the starting point, tie the twine tightly to the end post. As the plants continue to grow, add another layer of twine 6 to 8 inches above the last.
Do I need to prune the plants when I stake tomatoes?
Pruning outside shoots or suckers can be beneficial with any training system but is important for those grown using the single staking method. Pinching out the sucker that forms where the base of the leaf attaches to the stem (the leaf axil) can reduce the mass of the plant, making it easier to support. This also focuses the plant’s energy on fruit production rather than growing suckers. Start pruning suckers in late June after the first flower clusters begin to form but while they are still small.
While all tomatoes can benefit from pruning, determinate varieties require less pruning than indeterminate types. Removing suckers can improve airflow, reducing disease issues. However, fruit is more susceptible to sunscald as the removal of sucker growth reduces the leaf canopy. Allowing suckers that form later in the season higher up on the plant to grow will help shade fruit and reduce sunscald.
Yard and Garden: Staking Tomatoes
Aaron J. Steil, Consumer Horticulture Specialist
Iowa State University Extension and Outreach
June 22, 2022