Pruning Tomato Vines

Growers at Epcot in Disney grew this incredible tomato "tree" using hyrdoponics. This single plant yielded thousands of fruit.

It’s always a good idea to plan for success with your tomatoes. If you’re growing beefsteak tomatoes, you’ve got to consider that a mature tomato can easily weigh one pound. If you have a good harvest (fingers crossed!), you could end up with 20 pounds of ripe, precious fruit hanging off your tomato plant at any given time.

You don’t want to lose it, so you’ll need to provide support and train the plants. Hopefully, you’ll have a support system in place BEFORE you plant the tomato, so this article is about how to train tomatoes for the best harvest.

Training tomatoes begins just a few weeks after they’re planted. As the plant grows, small shoots will emerge from the axis between the leaves and the main stem. These are called suckers (or axial shoots or lateral shoots). Pinch these suckers off as the plant grows. Be merciless and thorough—don’t let your plant bully you into sprawling all over the place. You are the boss.

Pruning is good for several reasons. It allows sunlight to penetrate deeper into the plant, keeping it dry and disease free. It also encourages bigger fruit and aids in ripening since a well-pruned plant allows sunlight to reach the ripening tomatoes.

While you’re pruning, you should also be tying up the plant. Use twine or tomato ties to keep the plant firmly fixed to the support system. Remember that heavy clusters of fruit will form, so you might need to support individual branches as the season wears on. Try to keep the plant balanced if your growing in a cage so it won’t tip over when it’s heavy with fruit.

Even with pruning, your tomato might still try to grow into a monster and overrun the top of your support. Stop this by pinching off the growing tip when the plant hits the top of the support. Don’t worry—you will still harvest plenty of tomatoes.

As the season goes on, your indeterminate tomatoes will begin to yield fruit on a regular basis, starting from the bottom of the plant. Keep the plant healthy by regularly harvesting the fruit, trimming off dead and yellowing leaves and branches on the bottom, and removing any part of the plant that has been damaged by insects. Remove fruit with blossom end rot as soon as the condition becomes visible. And don’t forget that fertilizer: you might be able to stretch your season a bit by giving a shot of late-season fertilizer to encourage one last flush of flowers.

Once you get some practice training indeterminate tomatoes, you can do some pretty remarkable things. Tomatoes are actually perennial plants, so they’ve evolved to grow year-round. They’re only grown as annuals in most places because frost kills them. But greenhouse growers regularly get nine months of production from a single tomato plant, and in Disney World in Orlando, clever gardeners in the Land Pavilion Nestle Hydroponic Greenhouse trained a cherry tomato plant into a “tree” that grows up into a framework and bears tomatoes like apples. Overall, the plant’s canopy measures 24 feet by 30 feet, and it produced almost 900 pounds of fruit between May 2004 and June 2006. A similar “tomato tree” was exhibited at the World Exposition in Japan. Also grown hydroponically, this single plant produced more than 5,000 tomatoes. The world’s largest tomato plant measured more than 60 feet.

As a last note: one of the reason we train tomatoes is to maintain good hygiene. Crowded, overgrown, dense plants are more susceptible to fungal and bacterial diseases, especially in cool, wet weather. They provide more places for bugs to hide. If you ever have the opportunity to check out a professional greenhouse operation, notice how clean everything is. The plants are kept neatly trimmed of any yellowed or older leaves, there is excellent airflow throughout the whole growing area to keep the plants dry and disease-free, and the facility itself will likely be spotless.