You will eventually go into your grow room or garden and notice your tomato plant leaves curling up. The key to correctly identifying the issue causing the symptom before administering a solution.
Even though you may not know what is causing the problem, it is certain that it is serious if it is indication a lack of health.
The leaves of our plants give us a lot of information about them – we can use them to identify nutrient or pH problems, for example. This is also the place where you will find common pests and diseases, as they love to eat these.
Our plants’ leaves may start changing when they suffer from environmental stress, either by heat or changes to their atmosphere. When a plant has problems, it is often difficult to tell what is causing the issue when the symptoms are visible only in the leaves.
Don’t worry, we will teach you everything that could be causing your plant’s leaves to curl up in the next few minutes. Then, we’ll explain how to remedy each potential cause.
What Tomato Leaf Curl Up Could Indicate
Many problems that arise in a grow room or garden will show similar symptoms in the plants.
This makes keeping our plants healthy tough. However, we will go over how to fix the problem later. We need to explain the reasons this might be happening in the first place.
Rule Out Excessive Heat & Light
Tomato leaf curl up is typically caused by excessive heat or light energy. There are two specific instances in which this is a common occurrence:
- Outdoor growing during the summer in hotter climates
- Indoor growing when young plants are exposed to intense grow lights for the first time.
If your grow lights are too close to your canopy or temperatures exceed the ideal range for plant health, this can cause heat and light stress in plants.
You need to constantly monitor the temperature if you’re growing indoors, especially if you’re using MH/HPS grow lights. Keep the growing space between 70-80 degrees Fahrenheit. If you adjust the temperature, your plants will recover quickly.
If your plants are Curling more towards the center, it is likely that they are being affected by the heat from your grow lights.
Root Problems Related To Overwatering
The most common mistake novice gardeners make when growing tomatoes is overwatering their plants. Too much water can cause the leaves of tomato plants to roll up, a condition called leaf roll. This can cause problems such as root rot, early blight, fusarium wilt, and slow plant growth. One of the symptoms of overwatering your plants is that the tomato leaves start to curl up. If you notice your tomato leaves rolling, changing color from green to brown, and drooping, it is likely that your plant has root rot. Make sure to check the moisture of the soil before watering it again, using either a moisture meter or your fingers. The soil should be allowed to drain completely before being watered again.
You can tell if a plant is overwatered by looking at the plant in general. You can tell if a plant is heat stressed by looking at the plant in general. If the plant is wilting and overall droopy, it might be root problems from overwatering.
Extreme Humidity Can Cause Tomato Leaf Curl Too
Leaves curling up can also be caused by extreme humidity in the grow space. Many growers struggle with grow tent humidity in particular.
If you have a lot of plants in a small space, it’s hard to avoid problems.
If you’re not sure what’s causing problems in your grow, you can check with a hygrometer.
To maintain a healthy grow environment, humidity levels should be kept at 50-70% during the vegetative stage and 40-50% during flowering.
If you don’t take care of this problem, it can cause a lot of different fungal problems. Fungal diseases like bud rot, powdery mildew, and septoria leaf spot can quickly ruin your crop and force you to start anew.
Check For Sucking Pests On Your Leaves
When tomato plant leaves curl up, it usually means they are surprised or dehydrated. The issue could be related to pests if you don’t believe it to be related to your environment – heat or humidity.
Pests that suck the juices from your foliage can cause your plant leaves to curl up. There are a few pests that come to mind, such as aphids, thrips, and whiteflies.
An infestation of these is more common when growing outdoors, but it’s not difficult to have one develop indoors as well.
You can prevent your environment from becoming contaminate by growing in a tent and keeping it sealed.
Even after taking all the necessary precautions, you can still unintentionally bring bugs into your grow room by bringing in infected plants or on your pets.
You should check the undersides of your leaves regularly so you can discover pests early, before they establish a large population.
Nutrient & pH Related Problems
There are four potential causes that have been mentioned so far that are relatively easy to get rid of or fix. The final potential reason your plant’s leaves are curling upwards could be a lack of nutrients or an incorrect pH level. Different deficiencies can cause leaves to curl either downward or upward. There are a few deficiencies that come to mind, like phosphorus and nitrogen. It isn’t effective to try to improve the situation by increasing the amount of nutrients you give the plants. If one of the nutrients is not being absorbed properly, it might be because the pH is off and needs to be adjusted to the ideal range (between 6-7).
There are also relationships between nutrients where one nutrient can either enhance or inhibit the absorption of another nutrient. Additionally, there are ideal ratios of nutrients that you should be aware of. This issue can be ruled out by following your feeding chart and adjusting your pH before feeding.
One less common reason for leaves to curl up can be from a virus. The ToMV and TMV both lead to declined growth in the tomato plant, and produce similar symptoms such as curling and discoloration of leaves. When young, tomato plants may have impeded growth with miniature leaves that coil upwards. Viruses are spread through human activity, such as from the gardener’s hands from one plant to another. There are many disease resistant varieties of tomatoes that can handle viral strains. For example, there are varieties of hybrid tomatoes that are resistant to diseases, such as “Health Kick” and “Sophya.”
The Tomato Yellow Leaf Curl Virus was first identified in a greenhouse in California in 2007. Although yellow leaf curl virus was found in other parts of the world, it was not introduced to the Americas until the 1990s and has since had a severe outbreak in Mexico that devastated fruit production during the 2005-2006 growing season. The virus inhibits the plant’s growth and fruit production. The yellow leaf curl virus is a plant virus that is spread by sweet potato whiteflies. This virus can cause problems for a range of host plants. Whiteflies cannot survive in cold climates, so they will not be a problem for most growers in the United States and Canada. The most obvious symptom of this infection is when leaves start to curl upwards and the veins turn yellow.
Remedies For Tomato Leaf Curl
Master growers can tell the difference between plant problems that have the same symptoms. For example, we already mentioned that tomato plant leaves curling up could indicate excess heat in the grow room, but could also indicate issues with watering, humidity, or even a pest infestation.
One could addresses each potential issue one by one, waiting for things to change.
Here are some tactics that you can use to fix each of the potential causes that we mentioned above.
The most common environmental cause of leaf curling is usually treatable. You can think of leaf curling as a way that the plant is communicating that something is wrong. Check the growing conditions around the plant. To check the soil moisture level, stick your fingers in the soil up to the second joint. Then, throughout the day, pay attention to how much direct sunlight the plants are getting and how hot it is outside. These plants need good drainage and consistent watering. It is better to water your plants deeply with a soaker hose on a hose timer, or by hand, rather than simply sprinkling water on them from the top. Tomato plants are susceptible to fungal infections and it is important for the leaves to stay dry to prevent the spread of the infection. Apply a thick layer of mulch around the plant to help keep the soil moist.
Tomatoes can be negatively impacted by high temperatures, high humidity, and heavy rains. Tomato plants can also get sunburnt! Depending on the cultivar, tomato plants can start to experience sunburn when the temperature rises above 38 C. A 30% sunblock shade cloth is a good way to protect your plants and these shade cloths can be reused year after year.
Tie the shade cloth to the tomato stakes and spray them with a fungicide to prevent fungus. The cloth can stay over the plants for the entire growing season, depending on how many hot days you may have. Pests target unhealthy plants, so keeping your plant healthy is the best way to prevent pests.
Tomatoes are hardy, fast-growing vining plants. When planting indeterminate varieties, be aware that they will grow very large and will require some type of support structure. No matter what technique you use – be it stakes, cages, or trellises – tying your plant to the support structure can help reduce or stop wind damage. Cut off any excess suckers and lower leaves to enable better airflow. Prune leaves that are infested with aphids or broad mites as a way to control their population.
Besides pruning, you can also get rid of aphids or broad mites by using a strong stream of water to wash them off of the plant. It’s best to spray the water early in the morning so the leaves have plenty of time to dry off before it gets warm. If the infestation is moderate, neem oil or insecticidal soap can be used. If the infestation is severe, pyrethrins can be used.
When Treatment Fails
There are times when no matter how much effort we put in, we cannot save a tomato plant. This is why having a few spare plants is important, in case the ones you have planted in your garden don’t do well. If you cut off any tomato leaves while pruning, you can stick them in water to grow more tomatoes. If the weather is not good for the plant and it dies, you can compost it.
You need to pay attention to the main causes of death before composting. If your plant is infected with a leaf curl virus or suffers from herbicide damage, don’t compost it. The virus or chemicals can stay in the soil and be passed on to other plants.
Tomatoes are one of the most commonly grown plants, and they take the pride of place in many gardens. No matter your taste, there is a tomato plant that will suit you. Heirloom varieties are stunning and hybrids are very productive. There is nothing better than the taste of a tomato that has been picked straight off the vine. However, tomatoes can be difficult to grow.
Some of the most common reasons for tomato leaves curling up are due to weather, pests, or lack of nutrients. We’ve given some suggestions on how to fix the issue.
This is usually caused by too much stress on the plant, mistakes by the grower in terms of giving the plant too much water or nutrients, or an outbreak of pests or fungi.
Now all that is left for you to do is to look into your own grow operation. You need to be careful and have a good plan to fix the problem in your garden or room where you grow plants.
Hydrobuilder is the best place to get all the supplies you need for your garden and grow room, and you can get the best products for less! Growers from all over the world keep coming back to our world-class service again and again.