How to make your tomato plants thrive this summer

Tomatoes are a firm favorite among our gardeners! Delicious raw in fresh salads and salsas, slow-cooked in rich tomato sauces for pasta, or preserved as a treat to enjoy this winter, everyone wants to grow their own succulent tomatoes. But, especially once they heat peak fruiting season, tomato plants can get OVERWHELMING. Here are a few tips to help yours thrive this summer.

Pruning and Suckering

Why Prune? 

  • Pruning is good for your tomato plant - they’ll put more energy into growing fruit if they’re not distracted by pushing energy into leaf growth!

  • Tomatoes on the ground are susceptible to disease and getting snatched up by critters

  • You want AIR FLOW between your tomato leaves to stave off mildew and disease 

  • Pruning keeps things neat so you can easily access your tomatoes!

When/what to Prune

  • Prune throughout the summer

  • Prune indeterminate tomato varieties

    • These grow taller and wider, they require pruning 

    • Offer fruit over long period of time… 

    • Some typical varieties: Beefsteak, Black Crim, Martha Washington, German Johnson

  • Prune determinate varieties

    • More bush-like varieties, do not necessarily need to be pruned 

    • Ripen mostly at the same time 

    • Typical Varieties: Valley Girl, Celebrity 

How to Prune

  1. Find central stem (“lead”) - this is the main stem from which the rest of the plant stems off. It is the one you would use to trellis or stake up

    1. Sometimes there are multiple leads- if it is early enough, you can prune one or two off.  If they are too big, you can keep them both, but trellis them separately

  2. Find the first branch with flowers - all branches below this can be pruned, but nothing above it 

  3. To prune:  Use a harvest knife, kitchen knife, or scissors to cut the branch off at the stem.  Try to leave the smallest blemish possible- the larger the blemish, the more opportunity for disease and for the plant to have a hard time recovering. 

    1. You only want to prune off the main stem, never off the branches themselves 


  • “Suckers” are new low-fruiting branches forming at the intersection of a fruiting branch and the stem. While they will produce fruit, many people remove them to manage their tomatoes more easily. 

  • To Remove: if they are small, you can remove them easily by pinching them off.  If they have grown larger, you will want to remove them with scissors or a harvest/kitchen knife


Tomato Pests

Tomato Horn Worms

  • Caterpillars that prey on tomato plants in particular

  • Large and green with orange/red horn on bottom 

  • Often see them carrying their eggs on their backs 

  • Because of their size, it’s easiest to physically remove them 



  • Aphids are white/green bugs that suck moisture from the plant- extremely common with tomatoes, especially greenhouse tomatoes 

  • Ladybugs are their natural predators, so the more ladybugs, the better! 

  • Spray them off with a forceful hose or pinch off affected leaves/branches

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Tomato Diseases

Tobacco Mosaic Virus

  • Spread by insects or seeds or through touch by touching tomato plants while smoking cigarettes. 


  • Every year there is early blight and late blight. It travels by air among tomatoes, so once it comes to the area it is almost unavoidable 

  • Signs: Yellowed leaves with black spots, fast fruiting tomatoes 

  • How to care for them: blight unfortunately you almost cannot get rid of without intense chemical applications.  The fruits are still fine to eat, however, so enjoy them while they last! 

Blossom End Rot 

DIY Calcium Solution 

Take several egg shells, cook them over the stove until they start to toast up, crush them up and put them in some apple cider vinegar- leave room as they will bubble and fizz! Let them soak for a day or so, then take the apple cider vinegar solution and add it into a spray bottle with water (10:1 water to vinegar solution). Spray it directly on plant leaves.

Still have questions? Reach out to use at with your tomato puzzles!