Tomato Leaf Curl – The Ripe Tomato Farms

^{Jeff Favelle July 17th, 2023}

Tomatoes are amazingly vigorous plants and as the worldwide favorite backyard crop to grow, they are often the stars of our gardens. So when something goes wrong, or looks a little off, we tend to get a little ( a lot) panicky about the situation. Enter, the dreaded Tomato Leaf Curl.

Every summer, without fail, Tomato Leaf Curl is a constant concern

There are 3 main reasons why this occurs, with one being far more common than the other two. All are a physiological response to stress.

First, tomato leaves will curl upwards to protect the upper leaf side from herbicides or other chemicals. If your tomatoes we subject to a spray from the city or a neighbor, this could be the cause for curly leaves.

Herbicides and other chemicals can cause Tomato Leaf Curl

Another key cause of tomato leaves curling is the actual Yellow Tomato Leaf Curl Virus! This uncommon, but devastating pathogen is usually carried by a Whitefly species host. Not usually seen in home gardens, if detected and diagnosed, the infected plants need to be burned and disposed of, never composted.

*Yellow Tomato Leaf Curl Virus is not to be trifled with!*

Finally, the 3rd, and by far the most common reason for Tomato Leaf Curl, is the physical response to heat and/or drought. Tomatoes are amazing plants not only because they are vigorous and grow so well, but also because they are highly resilient.

In times of low moisture, tomato plants will curl their leaves in an effort to conserve moisture and lessen the amount of transpiration taking place. In fact, even when moisture is plentiful, but high heat and transpiration levels exceed the root’s ability to replace lost moisture, the leaves will still curl. The easiest way to tell that this is simply a heat issue is to observe the leaves in the morning. Leaf curl should have subsided over the coolness of night.

*Even in the presence of adequate moisture, tomato leaves can still curl*

Water your tomatoes in the morning, thoroughly, but not every day. Train the roots to go deep and downward to maximize their ability to resist and fight off drought. Don’t be alarmed if your tomato leaves eventually curl, especially on the hottest days, but do keep and eye on it as prolonged stress is never good for your plants or your harvests!

Check out the video below for more info!