The Simple 3-Ingredient Solution For Curling Tomato Leaves

Curling leaves on a tomato plant is an issue many people face. There are quite a few possible reasons why your tomato plant has curling leaves, and unfortunately, no matter the reason, it can negatively affect your plant and will need a solution, as curled leaves can decrease the fruit quality and yield. Curling leaves are often a sign of insects, herbicide issues, diseases, or environmental stresses, such as too much sun or wind. Depending on the issue that's causing your plant's leaves to curl, you may or may not be able to fix the problem. Herbicide damage and viruses, for example, cannot be treated,  while damage from wind should fix itself over time. It can be difficult to determine the exact cause of your plant's curling leaves and the ideal treatment, but some gardeners report having luck with DIY treatments. 

One suggested solution, intended to treat issues caused by environmental damage and fungal diseases, is a mixture of rice vinegar, brown sugar, urea, and water. For this treatment, 2 ounces each of rice vinegar, brown sugar, and urea are diluted in about 4 gallons of water and loaded into a sprayer. The solution is then sprayed evenly on the tomato plants. While there are some anecdotes of gardeners treating curling leaves with different combinations of these ingredients, the actual efficacy is hard to determine. Plus, some of the ingredients in this solution can cause even more damage if used incorrectly. So, before you start mixing together this particular solution, learn more about how it may or may not work for you.

Of the ingredients, rice vinegar has the least conclusive support. While there is some evidence of other vinegars working as antifungals on plants, there is not much about rice vinegar. If the leaf curling is the result of a fungal disease, then rice vinegar may help, but other vinegars, like distilled white vinegar, may be more effective. As for brown sugar, there is support for the benefits of sugar water applications to plants related to disease prevention. There is also evidence that brown sugar sprayed on leaves could assist plants by allowing them to absorb fertilizers more quickly. However, it is important to use brown sugar spray with urea to get this benefit. 

Urea is a common nitrogen fertilizer, and it can promote healthy plant growth, although it will probably not counteract the loss of yield caused by leaf curling. It is important to use urea correctly to prevent causing more damage, such as scorching leaves. Before you apply it, make sure you know how to properly apply urea fertilizer with a hose sprayer. Finally, spraying a strong stream of water on your plant, aside from the usual benefits of watering, can dislodge aphids that may be causing leaf curling.

Overall, this solution may be worth a try if you are out of options and do not want to toss your plant just yet, as there is some mixed evidence surrounding the ingredients. Just understand that it is not a guaranteed solution. If your tomato plants are still struggling, you may also be interested in some surefire ways to bring your dying tomato plants back to life.