Tomato DIY: Pruning and Trellises

This is the fifteenth in our biweekly series from Amy Pennington – urban farmer, founder of GoGo Green Garden, and author of Urban Pantry and Apartment Gardening – on how to start growing your own food, no matter how tiny your garden-to-be is.

Today: Amy teaches us to take care of our tomato plants, prune them fearlessly, and trellis them with simple household supplies.

— Amy

Come summertime, when the air is hot and the sun is high, everyone comes down with a little case of tomato fever. I’m not sure how this plant grew to such epochal proportions as to measure the success of a home gardener, but it has. Today we present tomato tips and tricks, from pruning for maximum yield to easy DIY trellises.

Pruning Those Suckers
Tomato suckers are the small sets of leaves that grow between the main stem and a leafy branch of a tomato plant. These suckers, if left to grow, become additional flowering and fruiting stems for the plant. That's good, right? Not quite. If allowed to bloom and fruit, these additional tomatoes will ultimately compete for nutrients from the plant. Over time, this lessens the overall chances of all the fruit coming to delicious maturity. Cooler and shorter seasons (like in the Northwest), cannot support such prolific tomato production -- but regardless of your temperature, all tomatoes do well with a little pruning.

Pruned tomato plants with a string trellis

Pruning, in this case, refers to snapping off those little suckers. When the stems are new and short (say, 3 to 4 inches) you can snap them off with your fingers by bending them back quickly. If you let them get much larger, it’s best to use a set of shears so you don’t tear the main plant stem in the process. Starting in early August (after the plants have some good strong growth and the weather is consistently warm) I snap off suckers -- no hesitation, no regrets -- from the top half of the plant. (If you planted a smaller tomato variety or cherry tomato plant, leave more suckers on the plant. Because cherry tomatoes are smaller, they ripen faster and the plant can support more production.)

In addition to trimming suckers, now is a great time to prune about 30% of the green leaf stems from the tomato vine. This sends the plant's energy into fruit production, rather than upward growth. This also allows for air to pass through and for sun to shine on the fruit, which helps develop sweetness. More practically, pruning also allows a gardener to clearly see when tomatoes are ripe.

Be aggressive and fear not -- pruning will seldom cause damage to the plant or overall tomato production. Our "job" as home cooks and gardeners is to produce the most luscious tomato for our table. Keep that in mind, and you won’t have a problem getting rid of suckers and excess leaves. One last note: some people (like me) find the leaves of tomato plants highly irritable to their skin, especially on prolonged contact. For this reason, I always, always wear gloves and long sleeves when dealing with tomato plants.

A clever fence trellis

DIY Trellises
A structured tomato trellis offers support to climbing or tall plants and is perfect for maximizing and managing your space -- they keep tomato stems from breaking and allow for pruning. I know everyone loves tomatoes, so now is the time to get in the garden and focus on building tomato supports, if you haven’t already!

Perhaps you’re one of the many who purchase tomato "cages," but find that the plants are growing well over the confines of the cage and dragging it down. I’ll be honest and admit I am not a fan of tomato cages. Instead, I build a support system of bamboo in all of my tomato beds. DIY trellising is uber-efficient and less expensive. It also allows for easy pruning, good air circulation, and good fruit maturity, as it allows sun to sit on individual tomato fruits, ripening and sweetening them up. There are lots of other options for trellising, as well – re-using a fence, for instance. If you have supportive items like this around, use them. If not, build your own.

To Build: You need 5 lengths of 6-foot bamboo. Crossing two pieces of bamboo, tie string about 5-inches down, creating a small “X” at one end. Once tied, splay the bamboo apart, making a large “X” – these will act as the foundation for the trellis. Do this twice and position the the bamboo legs about 5 feet apart in the bed. Position the remaining piece of 6-foot bamboo across the frame and voila! A super durable, strong trellis in which to trail over vining plants.

To Support Tomatoes: Use garden twine and loosely make a knot around the main stem of the tomato, winding the string up to the top of the bamboo and tying off. Do this in one or two places along the main stem, gently twisting the tomato plant around the string for extra support and VOILA. Tomato support!

Watering Tomatoes
For heat-loving tomato plants, it’s smart to water in the morning before you leave for work. Watering in the morning leaves time for plants to soak it up before the heat of day and evaporation take over. Watering in the evening results in a drop in soil temperature which these heat-lovers do not appreciate. You wouldn’t like to go to sit outside in wet socks at night time, would you? Same, same.

Keep us posted on all of your tomato successes and failures. Have a great tip? Be sure to post it in the comments.