Tomatoes need to be pruned and trellised to thrive. I mean, you don’t have to, but if you do you will get WAY more fruit, and that’s the goal, isn’t it?
Pruning should start nice and early in the season, before those suckers get out of hand. If you don’t do this early, the suckers will grow quite thick, and fast, and it won’t be easy to see which is the main stem & growing tip, and which is the sucker. If you’ve waited too long, the suckers may even have bloomed flowers on them. But don’t worry, cut them off! Its better to sacrifice some fruit, so you don’t get too many leaves and small green tomatoes, which will take forever to ripen. All in all, pruning the tomato’s suckers will let the plant’s energy and hormones go into making small green tomatoes into those big, luscious, juicy, red (or purple, or orange, or yellow, or zebra green!) tomatoes.
The sucker is actually a new stem that comes up between the branches. You simply want to pinch it off, using your thumbnail. If it’s gotten quite girthy already, you can use your pruning shears as not to damage the rest of the plant. I like to start at the bottom of the plant, and work my way to the top. Once I get there, sometimes it’s hard to see which one is a sucker, and which one is the growing tip. If you’re not sure, its best to leave the ones close to the top so you don’t mess up. Don’t worry, the sucker will show itself within a few days, and you can pinch it off then. And I also never pinch the top sucker off before I trellis my tomatoes anyway. I will explain this in better detail below.
Usually once you pinch the sucker off, that particular joint on the plant should not grow another sucker. But this is not always the case. I find that with heirloom tomatoes, even if they are labeled “vine” and not “bush” varietals, the joints are sometimes relentless in throwing up more and more suckers. I just keep pinching & snipping every few days, as I don’t want my plant to get too big & leafy. Keeping the plants trim also allows for good airflow, which helps keep mould spores at bay, and more sun exposure on the fruit itself.
There are many different ways to trellis your tomato plants. You can use cages, stakes, or even a simple fencing system. But my favourite is using a string. Yup! A string. It sounds too simple to even work, but it really does.
With over 50 tomato plants in our greenhouse this year, the last thing we want to be doing every few days is tying the plants up to our trellis. Instead, the farmer puts wood lath up onto the greenhouse support trusses, and ties them in. Then we tie bailing twine from the lath, and dangle it down over each tomato plant. Then starting from the top of the plant, I simply wrap the bailing twine around the stalk of the plant, down to the soil line. I make sure that I leave a little slack, though, because as the plant grows taller, we will continue to wrap the top of the plant around the twine. This will need to happen every 2-4 days, depending on their growth.
As I mentioned above, I don’t snip or pinch the top sucker off of the plant before I wrap the plant around the string. The reason for this is because, once in a while, you might snap the growing tip off accidentally. If this happens, then you can continue to grow your tomato vine from this very handy sucker that you have conveniently left alone. Leaving that top sucker in tact until you wrap your plant is actually an insurance policy. But once the plant is wrapped, and in place, you can, and should, remove that sucker.
One last note about setting up the twine: you would think that you have to tie the bottom of the twine to the base of the tomato plant. This is not true. Actually, I advise against it, for two reasons. Firstly, because as the tomato grows, and becomes heavy with fruit, what you thought was “leaving enough slack on the line”, isn’t. All of a sudden, the twine is tight, and getting that growing tip wrapped around becomes tricky, and you will risk snapping it right off. By not tying the twine on the bottom, it leaves you some space to move the twine up if you need a little more slack down the road. Second, if you tie the twine, it may be loose enough while the plant is small, but gets tighter around the base as the tomato’s stalk becomes thick. If you don’t notice, you risk cutting off the tomatoes circulation and water supply. The tomato plant itself is a quite sticky plant, with tiny little hairs all over it. Those hairs surprisingly provide enough friction against the twine to hold itself up.