I am clearly not a professional farmer of tomatoes, but several weeks ago the little gardeners and I took a trip out to a local farm to pick strawberries and also to pick the brain of some of the folks there on how to grow tomatoes well. And I found out that one of the most important jobs is to prune tomato plants well. Who knew?!
Why Prune Tomato Plants?
Each year we grow various types of tomatoes in our kitchen garden, with some years yielding more than others. But I wanted a more consistent outcome this year. Instead of large bushy plants that grew some tomatoes over the summer, I was looking for an abundant harvest that would put us knee-deep in tomato sandwiches well into August. (Can someone pass the Duke’s mayo??)
While on a tour of the farm, we were able to see the greenhouses where the tomato plants were growing (since we were still getting some frost at night), and what I saw were tall and lean plants heavy with bright green tomatoes already. Clearly I needed to know what I was doing wrong, because my tomato plants never grew this tall, or produced so much fruit at one time.
So I did what any good gardener would do… I asked for help! There’s no shame in asking someone who clearly knows what they’re doing for a little bit of advice, and here’s what I learned about pruning tomato plants for a better yield:
- Bushy is not Better– While having a full and large tomato plant may look (and smell) heavenly, the plant is expending so much energy on those leaves and stems that it isn’t able to use as much on the business of growing fruit. I’ll be putting my tomato plants on a bit of a diet this year, and trimming back a good part of the bushy limbs.
- Don’t be a Sucker- Those little shoots that pop up right where a limb comes off of the main trunk is called a sucker, and it can literally suck the resources that your plant could be using for tomato growing. So pinch those suckers off before they get too big and become an actual limb themselves. Here’s a great image from the University of Montana of what a sucker looks like:
3. Don’t be Afraid to Cut- This was something that was stressed to me on my farm tour. Pruning a plant for the first time can be a bit anxiety-inducing, but Ms. Kelly guaranteed me that the plant would survive and continue to grow, and she has been right so far! I purchased two of their younger tomato plants (an heirloom Cherokee Purple and a Better Boy) and brought them home. After a two-week wait to be sure there were no more frosts in the forecast and hardening-off the plants, I planted them in our garden. After a few days, I gently pruned them, since I didn’t want to shock them so soon after being moved.
How to Prune Tomato Plants:
Per her advice, this is my pruning technique:
- Trim up the lower limbs if there are no tomatoes growing there. I actually trimmed until I got to a branch with blossoms or tomatoes growing there.
- Keep one main trunk line. In the past, my tomato plants would grow large and by the end of the summer, I’d have several main (large) trunks, so this year I’m keeping my plants pruned to one. This also makes staking simple, since I’m not confused about which main trunk to stake.
- When blossoms/fruit begin to grow, prune back any limbs/leaves growing off of the same branch that are not producing fruit. This helps the plant exert its energy on the fruit. (The branch below also had a few smaller branches growing off of it with leaves, and I pruned those off once the flower cluster started developing.)
If you’re planning to grow tomatoes this year, I suggest plenty of consistent water and pruning! With more pruning, you may also notice that your plants are taller, so be sure to grab a tall stake (we got a coated one from Lowe’s that’s about 8-feet tall, or you can find some here) and gently tie your main trunk as it grows. And I stress consistent watering because fewer limbs mean less places for water to go, so tomatoes splitting could be more likely if you aren’t watering your tomatoes consistently, then give them a gallon.
I’ll be sure to update the blog as tomato season progresses to let you know how this heavier pruning method works out. Happy Gardening!