How-To & Diy

Tomato DIY: Pruning and Trellises

August  7, 2012

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.

Shop the Story


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.

DIY Tomato Trellis
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.

DIY Tomato Trellis
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.

DIY Tomato Trellis
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.

DIY Tomato Trellis
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.

See what other Food52 readers are saying.

  • Jeremy Bauserman
    Jeremy Bauserman
  • The Solo Cook
    The Solo Cook
  • Amy McKinley
    Amy McKinley
  • Amy Pennington
    Amy Pennington
  • winegirlnc
I am a cook and food writer, author & gardener who is passionate about the environment, using sustainable resources, reducing my impact on the earth and making conscious food choices that are both smart for the planet and taste fantastic. When I'm not knee deep in dirt growing food, you can find me in the kitchen where I'm likely standing over a canning pot or staring up in to my pantry deciding what to make. In the gardens, I have a business gogo green garden, wherein I build, plant & tend edible gardens for folks in their urban backyards. I also launched a garden-sharing website in 2009 that connects urban gardeners to unused garden space across the country - Check it out!


Jeremy B. May 9, 2015
Do you leave a little slack in the string of your trellis so you can continue to wrap it around the plant as it grows?
The S. August 23, 2013
Great suggestions on tomatoes Amy. I always enjoy reading your thoughts. I just wrote some tips last week such as go by feel rather than color to determine ripeness.
Amy M. September 30, 2012
How long do you expect tomatoes to grow in Colorado this summer? Until it starts getting cold (which looks to be heading towards us the first week in October)? Do you ever cover your tomatoes to try to make it through to the next warm spell or is the first time we freeze it for Colorado tomatoes? This is my first year with a Colorado garden and I have hundreds of green tomatoes right now with 38 degree weather predicted in the coming week and I'm not sure if I should pick all the fruit and let it ripen indoors or if I can try to put blankets over it. Thoughts? Advice?
Amy P. August 17, 2012
This was a great question from a reader, so I'm posting here:


I live in Denver- I have 6 tomato plants and the cherries have doing well. The smaller tomatoes like the green zebra and plums are starting to grow/ripen too, but the other larger tomato plants either make flowers that dry up and fall off or have no flowers at all! They are all heirloom which I know can be tricky. The plants themselves all look amazing and I've never had this issue. Any ideas on how to help them? I can't bare an end of summer tomato-less depression!

Oh- and I was good at removing those suckers earlier in the summer, but did not think I could prune them so big- so I can do that now and see if it helps. And by removing the green leaves do you just mean nip off lots of the leaves or are there stems that only produce leaves and not fruit?

Thanks! A timely article.

Apologies for the tomato delay. Happy to hear your smaller fruits and cherry tomatoes are coming in! Sorry to hear about the fatty heirlooms. It could be a number of reasons, so I can't pinpoint for sure. Basically, it speaks to the plants being stressed in some way - too hot for too long/too cold for too long/watering too much or too little. There may also be a nutrient deficiency - have you ever fertilized the plants?

As for pruning, yes there are stems that are just that - stems that don't bare blossom or fruit. You can take those out! And as it's late in the season, now is the time to start removing any blossoms that are just coming in - there isn't enough time to produce full mature fruit and it's better for the plant to spend energy maturing any that are already formed.

winegirlnc August 7, 2012
How do you keep the squirrels (and other critters) away? I've resorted to chicken wire, but it makes it a giant pain to get to the plants for pruning, picking, etc.
aargersi August 7, 2012
we have to enclose everything in bird netting or deer, squirrels and especially mockingbirds will get it. It's a pain in the rump but it works.
aargersi August 7, 2012
I have been wondering about pruning for quite awhile, and have read mixed opinions, but I think you have me convinced! My tomatoes are long gone (ours peak May / June and then get completely sunburned by July - time for fall planting here!) but next year I will get after the suckers. What about topping cherry tomatoes? Mine get ridiculous, seriously 10-15 feet tall, then flop over (I have them in 5' hog wire cages that Mr L built) and I wonder if I should chop them back a bit next time ....