Tomato Plants: how to get more fruits

Whether you are new to gardening or you are a veteran, I am sure you have heard of tomato suckers and how they might be impacting the growth and yield of your plant.

But today I would like to dispel this myth once and for all, and with some good scientific data to back it up.

But let’s start from the beginning

The Anatomy & Physiology of Tomatoes

Tomatoes are fruit bearing plants who often develop a lead stem (the main) and side branches, where flowers, and eventually fruit, develops . Some varieties will have more than one leader.

The main steam is what allows the plant to grow vertically and will thicken with time as the plant becomes stronger and focus on building structural support. Then, side shoots are produced and these branches grow to become the parts of the plant that will develop flowers and eventually our juicy tomatoes.

In between these side branches and the main stem, we have what’s called “suckers”, which are a different type of branches that also grow to produce leaves and fruits.

For some reason, it became a widely spread myth that these branches are notoriously bad and therefore should be removed. But have you ever thought why and if this truly makes sense for a home gardener?

The tomato paradox

Plants use photosynthesis to grow, and the more leaves they produce the more they are able to photosynthesise, and thus produce what is called “photosynthates”. These compounds are used by the plant for various functions, including producing flowers and fruits.

However, more leaves also mean more need for water, more need for nutrients and so on. And here’s where the paradox begins:

If on one hand it is good to have multiple leaves to photosynthesise more, on another hand multiple leaves also require more energy to support all that growth.

Additionally, when the branches start producing flowers, each of those flowers will also require large amounts of these photosynthates to become fruits. Thus, the more side branches that produce flowers, the more energy portioning the plant will have to do — fruits now have to share the energy available, and therefore grow less.

And here’s where the “remove your suckers” arc begins.

Commercial Production: why growers prune and manage tomatoes the way they do.

Because we know the science behind energy allocation in plants (see reference list), it makes sense for growers to prune their tomatoes to produce larger fruits per plant! At the supermarket, consumers prefer larger and juicer fruits, so for the grower is more advantageous to have plants with these traits.

Commercial Tomato Growing: notice how most of the leaves have been removed where the tomatoes are growing.

And if you are a attentive reader, you will have picked that I mentioned LARGER FRUIT PER PLANT, not per area. The reality is that removing suckers allow for the plant to divert energy into fewer fruits and make them bigger and juicer, but there’s a cost to production in terms of numbers.

The way growers counter that is by planting more plants per square metre, specially because pruning allows for more space and less diseases.

Homegrowers: what should you do?

You’re not a commercial growers, nor do you have huge machinery. The reality is that you’re often growing 2-5 plants maximum per season. So, instead of focusing on larger fruits per plants and going crazy trying to keep up with new suckers coming out every 10 days, just relax and enjoy.

It is true, you will have to prune some suckers regardless because otherwise it may become a problem: reduced air circulation, too nutrient intensive, etc.

But you do not have to be meticulous about it — enjoy the journey. No all information we see online is true, and not all the ones that are true are applicable to your circumstances. So be critical and filter good advise that isn’t tailored to you.

Above all, experiment. Gardening is supposed to be fun, and you can worry about scaling production once you have enjoyed your first homegrown salad!

Happy gardening

Reference list:

Ahmad, H., Yeasmin, S., Rahul, S., Mahbuba, S. and Uddin, A.J., 2017. Influence of sucker pruning and old leaves removal on growth and yield of cherry tomato. Journal of Bioscience and Agriculture Research, 12(02), pp.1048-1053.

Ara, N., Bashar, M. K., Begum, S. and Kakon, S. S. (2007). Effect of spacing and stem pruning on the growth and yield of tomato. Int. J. Sustain. Crop Prod. 2, 35-39.

Bertin, N. (1995). Competition for assimilates and fruit position affect and fruit set in indeterminate greenhouse tomato. Ann. Bot. 75, 55-65.

Cockshull, K. E., Ho, L. C. and Fenlon, J. S. (2001). The effect of the time taking side shoots on the regulation of fruit size in glasshouse tomato crops. J. Hort.Sci. Biotechnol. 76, 474-483. https://doi.org/10.1080/14620316.2001.11511396