Gardeners Cannot Agree About Pruning Tomato Plants

There is a lot of information available about pruning tomatoes. And there is just as much disagreement about what type of pruning should be done, why, and whether pruning tomato plants is effective. I have tried it all and come to my own conclusions, and I urge you to do the same as you gain experience with growing tomatoes. A review of the “reasons to prune” can help you to evaluate for yourself.

Pruning Reduces Disease

This is true, appropriate pruning will improve air flow to help minimize fungus and disease. Pruning the lowest branches of your tomato plant will reduce foliage exposure to soil borne diseases by eliminating soil contact and reducing soil splash. Remove lower branches of short bushy determinate plants up about 10 inches from the soil Indeterminate plants can be pruned as much as 18 inches from the soil. The space at soil level also makes it easy to apply water and fertilizer without splashing foliage.

Also remove all damaged and infected foliage and branches quickly. Be sure to use clean sharp garden shears to prevent spreading disease.

Pruning Increases Air Circulation

This is true. Good air circulation will help prevent moisture loving diseases. Your foliage will dry more quickly after rain or watering. Prune out wayward, wild, crossed or very close growing branches. I try to take branches with the fewest flowers forming for the least impact on production.

Pruning Will Ripen Tomatoes Quickly

Some gardeners believe that exposing the fruit to sun will ripen the tomatoes faster. I do know that the plant needs sun to ripen the tomatoes, the tomato itself does not need the direct sun. As a matter of fact they do best if not directly exposed all day. So I will call this one false. And pruning out excess foliage will reduce photosynthesis because you reduce the leaves that do the work, and decrease the sugar produced for sweet tasting tomatoes. Of course if your plant has become so bushy that no sunlight is getting to inner foliage, a bit of pruning might be helpful.

Prune for Bigger Tomatoes

Suckers, always a bone of contention among tomato growers. The general belief is that if you prune out the little suckers growing directly from the crotch of the main stem and a branch you will produce bigger tomatoes. But these so called sucker stems will also produce fruit. The more fruit producing branches you have, the more fruit of course. Some gardeners prune out all suckers, some prune out suckers they deem to be an issue for staking and supporting.

The only way to get bigger tomatoes is to reduce the number of fruits allowed to form on each stem. Remove all but one or two fruits on each stem. The remaining tomatoes will get all the energy and will be able to grow larger than many tomatoes sharing the energy.

Prune for Space Saving

Huge bushy determinate plants can crowd each other and probably should be pruned. The best approach though is to space them out better when planting. I do like to squeeze in as many varieties as I can, so if I do squeeze them in too tight, I may have to prune sprawling plants a bit. Indeterminate plants can just plain get too long for their supports sometimes. Then they start flopping over into its neighbors space, and may have to be pruned.

Whatever you decide to try, any pruning should be started early in the plant development and continued a little at a time as the plant grows. Ideally prune early or late in the day, midday heat can stress the plant and inhibit wound healing. Experiment and make up your own mind!