05/24/2024
Should you prune Tomato Plants?
Tomato pruning entirely depends on what kind of tomatoes you are growing. Determinate and indeterminate tomatoes have totally different growing patterns and fruit bearing abilities/patterns. Cutting away at a determinate tomato plant, beyond the absolute necessary bottom trim to decrease likelihood of soil-splash carried diseases, just decreases potential yield with each cut.
So! While most gardening group populations are extremely pro-pruning... I absolutely *hate* that their default answer is to tell people to start pruning like mad, without even asking what you're growing and considering if it's even *appropriate* for your plant.
Anyone that says to cut off suckers or cut back to a single stem, without asking more questions.... don't trust their answers. They don't know enough about what they're doing yet.
Now...
1. Do you know if you are growing determinate tomatoes or indeterminate tomatoes? If the little label for the plant didn't say, you can find out with a quick Google search.
2. Are you growing cherry tomatoes or a beefsteak variety?
3. Would you rather have more tomatoes overall, or would you rather have fewer tomatoes but bigger sized tomatoes overall?
1a. If you are growing a determinate tomato, the only pruning you should do is the universal tomato minimum: once tomatoes are about 12 inches tall or higher, remove all leaf-only growth from the bottom 6 inches. When the plant gets taller, you can increase that to the bottom 8 inches, if you want. This keeps wet dirt from splashing onto the leaves when you eater or it rains, as tomatoes are susceptible to a lot of diseases carried in the wet dirt. ALL tomato plants should get this done, no matter what. Vine growth and blossoms and fruit on the bottom are okay, it's just the leafy growth we worry about.
1b. If you are growing an indeterminate tomato, then we need to know if you are growing a cherry tomato or a beefsteak tomato plant.
Cherry tomato plants don't need to be pruned beyond the minimum bottom trim either. Almost all cherry tomatoes are indeterminate. They will put grow multiple additional vines (aka: the "suckers" although I hate that term... they're just more vines, same as pepper branches) that grow off the main stem, and each of those vines will ALSO produce lots of blossoms and fruit, while only needing the one root system and space for one plant. Pretty cool, right? You get the produce of multiple cherry tomato plants, all from one plant. No need to cut off the "suckers" unless you are deliberately trying to reduce the yield of the cherry tomato plant, which I guess some people actually want to do. Me? I want alll the cherry tomatoes I can get. Single-stemming cherry tomatoes is a commercial greenhouse technique to slimline the plant so they can fit more of them closer together for a commercial production, but they also prune off blossoms to get fruit clusters that are all ripe at the same time and the same size, and I don't do that either. Some things are practical for commercial production but not a family garden, after all.
If you are growing a beefsteak variety, this means we need the answer to #3.
3a. If you are growing beefsteak indeterminates, but care more about getting a larger number of tomatoes than getting fewer tomatoes that are larger in size... then only prune the minimum amount and let all the blossoms and fruit you can, grow.
3b. If you are growing beefsteak indeterminates and want the biggest individual tomatoes you can grow, even if you don't get as many as a result, then go with the single-stem method and once the tomato plant is about 1 ft tall, start watching the growth in the little "armpit" of where the leafy branches meet the main stem. There are some blossom clusters that can grow from that spot, so don't pinch or prune as soon as you see growth there... but wait until you can tell if it is a blossoming area growing from that spot, or if it is a new vine growing from that spot. You can let it get 3 or so inches long before pruning, it won't hurt anything to let it grow a bit so you can tell what it is doing. If it is a new vine, you can prune that spot off, to limit the blossoming area to only the central vine. You will get fewer blossoms (and therefore fruit) overall, but all of the plant resources will be dedicated to those that you leave alone.
It's kind of like how watermelons and giant pumpkins and such are deliberately limited to three or less fruit per vine, so the remaining ones hopefully get bigger than if they were growing a larger number and had to share resources.
On the opposite hand is how many people deliberately try to make pepper plants grow more branches so they will produce more potential fruiting areas off of a single plant.
If you are just growing a regular slicing tomato... I would just leave it to minimum basic pruning and see how many tomatoes your plant can make you. They generally aren't going to get any bigger than they would grow anyway, do single-stemming to force the resources into fewer fruits isn't really going to help you. It definitely won't help you make bigger cherry tomatoes lol.
So! There you go. A whole breakdown of the flow chart in decision-making for pruning tomatoes and whether it is appropriate for your goals.