It is a common misconception that it is inevitable for the lowest leaves of a tomato plant such as cherry turning yellow and fall off as the plant matures. However, this is not the case. However, according to Joe Masabni, Ph.D., who works as a vegetable specialist for the Texas A&M AgriLife Extension Service in Dallas, that is simply not the case. According to Masabni, an assistant professor in the Department of Horticulture in the College of Agriculture and Life Sciences at Texas A&M University, a healthy plant is one that is well maintained and is not stressed by disease or nutrition. A plant with leaves that are green from the bottom to the top indicates that it is healthy. Yellowing leaves are typically caused by an imbalance in the plant's nutrition or an outbreak of disease, although there are instances in which other factors are involved. The leaves on tomato plants can turn yellow for a number of reasons, including nutrition. According to Masabni, "nitrogen is the most common cause," and the reason for this is that people generally do not fertilize tomatoes enough. 
According to him, tomatoes are heavy feeders, which means the plant takes twice as much fertilizer as a cucumber does and even four times as much as beans do. This is because tomatoes have a larger root system than cucumbers do. If you do not provide the plant with a sufficient amount of nitrogen through fertilization, the older leaves may begin to turn yellow and, in many instances, may fall off. The reason for the yellowing of the older leaves is that they are passing on their nitrogen to the younger ones, which allows the younger leaves to continue living. The yellowing of leaves can also be the result of a lack of iron in the plant, however this symptom will be most noticeable in the leaves that are the most recent to emerge from the plant. However, a magnesium deficit can cause yellowing on the older leaves that looks more like speckles or spots than it does yellowing. According to Masabni, "these three, nitrogen, iron, and magnesium, are the most prevalent nutrient shortages producers should pay attention to and fertilize regularly for." It is important to keep in mind that if a significant amount of fertilizer is applied to the plant, the plant will also require a significant amount of water. 
"There is no perfect recipe for how much water your tomato may need, but a good rule of thumb is to do a moisture test where you place your finger several inches deep in the soil to test for moisture near the roots," he said. "This will give you a good idea of how much water your tomato may need." It's time to water if it feels dry, and as the tomato plants get closer to reaching full maturity, they'll need more and more water. If it feels dry, it's time to water. Even better, invest in a soil moisture meter and make its consistent monitoring a part of your watering routine. Simply put, the high temperatures and high levels of humidity that are typical in the state of Texas make it an ideal environment for the development of fungal diseases in tomato plants. Because of the favorable conditions for the spread of diseases, Masabni recommends using a fungicide protectant on a consistent basis, anywhere from once every seven to ten days to as much as once every fourteen days during dry years. "Spray on a schedule regardless of whether or not you believe you require it," he said. Fungicides are primarily employed for preventative purposes rather than as treatments for fungal infections. Therefore, this is a preventative measure that gardeners will want to implement before they notice any symptoms of a sickness in order to safeguard their plants against the affliction. 
Once the symptoms of the condition become apparent, it is frequently too late to treat it. He explained that the majority of infections caused by fungi and bacteria result in some form of yellowing. Powdery mildew, also known as early blight, is the type of fungal disease that occurs most frequently in Texas. It begins at the base of the plant and works its way upward as the plant's leaves fall off. The yellowing of the leaf is sometimes caused by physiological diseases. The yellowing effect can be caused by salt damage, which includes not only sodium chloride or table salt but also any excess mineral. If you are growing tomatoes in a container and the water you are using has a high concentration of salt, you should periodically water the container until it leaches out. This will allow the salt to move through the soil and flush out of the container. If you are growing tomatoes in a container, water the container until it leaches out. This will assist in preventing the building of those salts within the container itself, which is something that will be helped by doing so. Take extreme care when handling herbicides. According to Masabni, gardeners should avoid using Roundup near vegetable gardens since tomatoes are particularly sensitive to the effects of Roundup. 
The damage caused by Roundup to tomato plants results in a bleaching effect that moves from the inside to the outside of the leaf and affects the plant's most recent growth, including the youngest leaves and shoots. Vegetable problem solver and maintenance You will find a vegetable problem solver accessible through the vegetable resources link on the Aggie Horticulture website. This tool allows you to research solutions to a variety of issues that are typical in the state of Texas. He summed it up by saying, "The bottom line is that any sort of yellowing is not healthy." Even if you don't know what's causing the problem, you should pick off any leaves that have turned yellow and dispose of them properly in case they are infected with a disease that could spread to other plants. Take off that leaf, apply some fungicide on the plant, and cross your fingers that an early diagnosis will address the problem. 
When removing leaves, it is important to make sure that you remove them with clean hands and then dispose of the leaf in the appropriate manner. In order to prevent the transfer of illness from one healthy plant to another, you should properly wash your hands before continuing to work on other plants. Consider whether or not you have been applying fertilizer on a consistent basis. Is the plant the same height as it was a month ago, which may indicate that you need to add more fertilizer, or is it taller than it was before?
💰 Tenfold your income 💎