How are your tomato plants progressing? Experience any growth issues? If you’re reading this, your tomato leaves are probably curling.
Yes, it happens!
Tomato leaves can curl similarly to other vegetables. Should you be worried?
Tomato leaves can curl for various reasons. However, the main reason for curling is in response to the stresses the plant is facing. This can range from environmental stress, diseases, pests, herbicides, etc.
But there is a bigger question. Can tomatoes recover from leaf curling? The good news is that tomatoes can recover from leaf curl most of the time. Leaf curls in tomatoes can easily be remedied. There are only a few exceptions where leaf curls indicate something more serious.
Let’s dive deep and see the causes of tomato leaves curling and the steps you can take to remedy the problem.
Underwatering in Hot Weather
Underwatering is the main reason tomato leaves are curling. While tomatoes are easy to grow, they need the right amount of water. Too little water is never good for tomatoes.
Tomato plants that are actively growing and developing fruits have huge water requirements. When the weather is too sunny, the leaves fold to reduce the surface area exposed to the sun.
The lowest leaves on the plant are the first to be affected. As a general rule, tomato plants need at least 2 inches of water per week. However, the exact amount of water needed varies depending on factors like wind, humidity, heat, and soil type.
How to fix:
Try and water your tomatoes in a manageable and consistent manner. You can use a drip system as opposed to applying a deluge of water. If applying with your hose, use the lowest settings possible.
Water the tomatoes for 2-3 days during the summer. There is no rule on when to water your plants. You just need to ensure the soil is not too dry or too wet.
Lastly, make sure you water the roots and not the leaves. Water on the leaves can lead to the spread of fungal diseases. The leaves burn and attract pests.
Environmental Stress
Apart from water, tomatoes can also curl due to environmental stress. Wind and sun are the most common sources of tomato stress. Wind stress is very common when tomato plants are young.
This is the case, especially during the winter and spring season when there is a lot of wind. This can impact the development of tomatoes if the winds are consistent.
When they receive too much sunshine during the day, the leaves can curl. However, this should not worry you as they revert to normal at night.
Leaves can also curl when there is too much heat. Tomatoes are sun-loving plants. However, there is a limit to how much sun is needed. When temperatures go beyond 85 degrees F, tomato plants can be stressed and curled leaves.
How to fix:
One of the best ways to fix environmental stress is to position a shade over the tomatoes. You can use a cloth to cover your tomatoes on the hottest days.
You can also solve the issue by staking or using tomato cages. Make sure you use strong stakes and tie multiple parts of the stem to the stakes.
Over Pruning
Tomato pruning is very essential. It ensures that tomato plants grow healthily and produce larger fruits. However, over-pruning can stress out the plant and cause the leaves to curl.
There is a debate about whether to prune tomato leaves. Removing older and yellow leaves is ideal for efficient growth. But too much pruning can cause stress and make the leaves curl.
How to fix:
Avoid pruning determinate tomatoes at all once the first flowers emerge. This will impede growth, and cause curls and small fruit production.
For indeterminate tomatoes, practice gentle pruning by pinching suckers. This involves the removal of new growth between the lateral and the primary stems of the tomato.
Excessive Nitrogen
Using excess nitrogen can also cause stress on tomatoes leading to curls. Tomatoes require nitrogen, phosphorus, and potassium in certain amounts. Nitrogen helps with foliage growth.
But excess nitrogen can lead to excess foliage growth putting pressure on the plant. When planting your tomatoes for the first time, start by using a balanced fertilizer.
Once plants mature and start to flower, you can start adding fertilizer with more potassium and phosphorus.
How to fix:
Most problems with nitrogen will resolve with time once you stop adding fertilizer. Make sure you take time and learn the needs of your tomatoes before applying fertilizer.
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