Tomato Plant Leaves Curling? Know the 5 Causes

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JAKARTA - Planting tomatoes is often considered easy. In fact, planting any fruit or vegetable has its own challenges. Not only that, tomato plants also often experience problems, one of which is curly or curved leaves. Of course, any change in tomato plants is a concern and you have to do everything you can to fix it.

However, the most important thing is to understand what causes it and this is where you can overcome it. Quoted from The Spruce, Monday, August 5, here are the causes of curly tomato plant leaves. 

Planting tomatoes too early

Tomatoes can develop curly leaf if they haven’t been hardened off properly or if they’re planted when the weather is too cold. It usually starts with the lower leaves curling upward, then curling inward lengthwise. The leaves also become thick and leathery but usually remain green.

The solution:

Be sure to plant tomatoes only when daytime temperatures consistently reach between 70 and 75 degrees Fahrenheit, and nighttime temperatures don’t drop below 65 to 67 degrees Fahrenheit.

Heat, drought and wind

In very hot, dry, or windy weather, tomato leaves will curl upward to protect themselves from further water loss.

The solution:

If you live in a hot or warm climate, plant tomatoes in a location protected from strong, drying winds and with some afternoon shade. No matter your climate, always water your tomato plants well. When outdoors, tomato plants will need at least 1 inch of water each week from rain or watering. Water slowly and deeply, so the plants develop deep roots. Mulch around the base, so the soil stays evenly moist.

Nutritional imbalance

Tomatoes that are overfertilized with nitrogen may show upward-curling leaves, thicker and greener leaves than usual, and more leaves instead of fruit. Low phosphorus can also cause leaf curl.

The solution:

Once established in well-nourished soil, tomato plants will benefit from a balanced 5-10-5 fertilizer several times during the growing season. Avoid fertilizers that are high in nitrogen (the first number), or you will have lots of bright green leaves and fewer tomatoes.

The only reliable way to determine the nutrient content of your soil and how to correct the imbalance is to have a soil test performed in a specialized laboratory.

Tomato virus

Diseases, viruses, and pests can also cause tomato plant leaves to curl. Curling tomato plant leaves are often associated with poor fruiting, mottled leaves, stunted growth, and more. It can be difficult to pinpoint exactly what problem your tomato plant is facing, but tomato mosaic virus and yellow leaf curl virus are the most common. In many cases, these viruses are spread by pests in the garden. That’s why it’s so important to know how to get rid of greenhouse flies.

The Solution:

Since these diseases and viruses are often spread by garden invaders, you should try to eradicate garden pests as soon as possible. Try planting pest-repelling plants near your tomato plants, perhaps even using nematodes to your advantage. While you’re at it, you should also separate the diseased tomato plants from the healthy ones. This will prevent the spread and keep the rest of your plants safe from the leaf curl.

Exposure to weed killers 

Finally, the cause of tomato plant leaves curling is exposure to weed killer. If you are still using chemical weed killers, this has a bigger impact on your garden than you might think. However, exposure to weed killers can be the cause of tomato plant leaves curling.

Tomato plants are very susceptible to hormonal weed killers and using them on the other side of the garden can still affect them. If the slightest bit of residue gets blown onto your tomato plants by the wind, it can cause them to suffer.

As a solution, if your tomato plants have been exposed to chemical weed killers, there is not much you can do to help them. They may survive the ordeal, but they may never recover. So, it is best to continue caring for your tomato plants as usual and hope for the best.