Gardeners face each other off with pitchforks when it comes to this question… It’s a topic that’s almost as controversial as that other big tomato question: is a fruit or a vegetable? Discover both options regarding sucker removal here, the pros of each and our tips to make the choice that’s right for you.
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These are the small stems that grow wherever secondary stems and leaves connect. You’ll typically find one sprouting from the point where the main stem branches off into a secondary stem. It may also emerge from secondary stems, again wherever a leaf sprouts out on that same stem. If you let them grow, suckers can become extremely vigorous.
How do you recognize a sucker? It’s pretty straightforward: it won’t bear flowers, and so it won’t bear any fruit either. This is precisely where the name comes from: these branches suck a lot of sap, but don’t use it to produce any tomatoes.
Here is where the great divide appears: some think it’s crucial to remove them, whereas others find it better to leave them on the plant. Let’s focus on the reasons why each side thinks they’re right.
These make their decision based on the fact that these little stems consume an inordinate amount of sap, depriving fruit-bearing stems from their due share of nutrients. Removing them would thus allow a better harvest. Fruits grow larger, and they all more or less reach the same size. It’s said that they also ripen in sync, reaching maturity at the same time.
Gardeners who defend this idea state the simple truth about what these suckers are: stems full of leaves, every single one of which is fully dedicated to photosynthesis. Photosynthesis is the process through which plants create organic matter using sunlight. So it stands to reason that if you cut them off, you’re depriving the plant from a precious resource it could use to grow.
Lastly, it’s important to remember that tomatoes are plants that are particularly vulnerable to disease. Each cut is a wound that lets bacteria infect the plant. After all, since the beginning of time, nobody was there to pinch suckers off tomatoes and still they survived in the wild!
→ Special case: pruning cherry tomatoes
Both camps have solid arguments, and each way of handling suckers asks something different of the gardener. Here is what each approach involves and what it costs you.
| Approach | What you do | Main benefit | Point to watch |
|---|---|---|---|
| Pinch out every sucker | Remove the small stems as they appear at each leaf and stem junction | Sap goes to fruit-bearing stems instead, for a better harvest | Each cut is a wound that can let disease in |
| Full pruning (Technique #1) | Remove suckers and top the plant so only 4 or 5 fruiting stems remain | Less bushy plant, fruits get much more direct sunlight | More cuts, so more entry points for infection |
| No pruning at all (Technique #2) | Let the plant grow as it would naturally, keeping every leafy stem | All those leaves keep working at photosynthesis, feeding growth | Unpruned plants spread widely, so space them well |
| Try both and compare | Grow one plant pruned and a second one nearby left untouched | You get an answer that fits your own garden | You only know at harvest, when you count and rate the fruit |
Whichever column you pick, the decision is yours to test rather than to inherit.
If they’re still small and soft, you can remove them with your fingers, pinching them off. However, if you’re a bit late in removing them, better use a sharp secateur or pruning shears. Clean the tool and disinfect it before use. Best is to prune on a day without rain, so that you reduce the risk of fungal diseases appearing – that dreaded blight!
When pinching small side shoots, or suckers, from tomato plants, snap them sideways rather than pulling them downwards, because a downward pull can tear a strip of skin off the main stem.
Wipe and disinfect the blades between plants too, because sap left on steel carries tomato viruses from one plant to the next.
Tomato side-shoots (suckers) about a hand’s length root readily in damp compost or a glass of water, so the ones you pinch out can be grown on as spare plants.
More and more amateur gardeners rely on natural self-regulation to maintain their vegetable patch (to the point of not staking them, even). Apply this to tomato plants, and the conclusion is to leave the suckers on the plant, since removing them is a useless waste of time. If the plant catches a disease because of the pruning, it’s going to have to expend energy fighting it off – the exact opposite of what was intended in the first place!
Why not try both techniques out yourself? Grow one plant, diligently removing every single sucker you see. And then another, nearby, without removing anything at all. When harvest time abides, simply count the fruits and rate their quality. Which one fared best for you?
→ How to collect and save your own tomato seeds
For this technique, you’ll of course remove suckers, but there’s a bit more to it than that. It’s recommend to only keep 4 or 5 secondary stems that will bear fruits. To do so, you’ll have to top off or behead any plant that produces more that that number of stems. This reduces the bushiness of the tomato plant, and fruits will get much more direct sunlight.
Topping determinate tomato varieties is generally unnecessary, because they naturally stop growing once a terminal flower cluster forms, and removing growing tips can reduce the plant’s overall fruit set.
When you take the top out, cut just above a leaf rather than in the middle of a bare stem section, as the stub left behind dies back and invites rot.
Tomato and pepper fruits suddenly exposed by heavy leaf removal can develop pale, leathery sunscald patches on their sun-facing side, so when deleafing tomatoes leave a couple of leaves shading each truss.
This second method requires restraint on the part of the gardener: no pruning at all, simply letting the plant grow as it would naturally. In this case, it’s important to pay attention to one thing: space your tomatoes well. Indeed, when not pruned, tomatoes will spread over quite a large surface, a fact that many tend to overlook until it’s too late.
The ideal set-up for this is a cage-type stake. It’ll fare better than straight stakes or ladder stakes. This is due to the nature of tomato vines: they’ll grow so much that any regular stake will quickly be too short.
→ More on staking tomatoes here
