Why tomato plant leaves turn yellow? There are many reasons why the leaves of tomatoes turn yellow, and after reading these tips below, you will know how to deal with them.
Yellow leaves on tomatoes are a very common occurrence, such as too much watering or lack of fertilizer, which can cause yellow leaves, which of course should be dealt with promptly and carefully checked for insect or fungal diseases.
Yellowing tomato leaves are usually due to under or over-watering, as well as possible nutrient deficiencies and pest and disease infections.
Most cases of yellow leaves are easy to deal with, and it’s up to you to uncover the problem and diagnose the cause of the yellow leaves for your own care.
OVERWATERING AND ROOT ROT
Tomatoes are prone to poor growth if they are watered excessively frequently, the soil is wet for days or dry for long periods of time. Every time they are watered, the soil should not be allowed to become waterlogged and the soil should be kept well-drained, and if they are planted in the yard, they should not be planted in low-lying areas.
If you water too much, the leaves will easily water yellow and the color of the leaves will also become lighter. If there is a lot of water for a long time and the soil is often waterlogged, it will easily lead to a lack of oxygen to the roots, which will eventually lead to root rot and plant death.
If you find that the leaves at the bottom of the tomato rhizome become tender and yellow, it is caused by root rot, the bottom of the rhizome will appear brown or brown, the roots will become soft, and in severe cases, it will be paste.
Usually watering should be done with care, usually waiting for about 3cm (1.18inch) below the soil surface are dry, then give it additional water, each time watering should be watered thoroughly.
Once the root rot is more serious, you need to dig up the plants with rotten roots and discard the surrounding soil as well, do not leave them in the yard or pots.
Poor permeability of the soil, coupled with the soil is not loose, is also very easy to lead to yellowing of tomato leaves, in the process of planting tomatoes, you can fill in the soil with some well-rotted manure, or in the spring and summer growing season of tomatoes regularly add some organic fertilizer water, to help prevent soil clumping, to keep the soil loose.
Regularly filling in the soil with some composted soil will improve the soil. If the soil is already clumped, do not follow with watering, first loosen the soil properly, then sprinkle some powdered slow-acting organic fertilizer on the soil, or add some organic fertilizer water, all can improve the soil clumping.
LEAF SPOT DISEASE
Tomatoes infected with leaf spot disease is also very common, is infected with a fungal disease, in the soil is wet or air humidity is particularly high in the environment will be easy to breed, maintenance of poorly ventilated location, or tomatoes not set up a good rack, no is the main cause of breeding leaf spot disease.
Another situation is because the soil carries fungal diseases that lead to leaf spot disease, no matter what the cause, all you need to do is to promptly cut off the yellow leaves and promptly spray fungicides, such as common chlorothalonil or methyltobucin solution. Improve the ventilation of the environment and the bottom of the stems and leaves that are overly dense should be thinned out properly.
Be careful not to water the tomatoes at night, no water should remain on the leaves for a long time, and the location where the tomatoes are maintained should have more light every day.
Wilt is also a common fungal disease of tomatoes, usually caused by the protozoan Fusarium acnes, which infects the plant through the root system, hindering the tomato’s ability to attract water and causing the plant to wilt, rarely resulting in the tomato hanging.
After wilt appears, the bottom leaves of the tomato will continue to yellow and gradually spread to the top of the stem and leaves, eventually causing the entire plant to wilt.
To prevent wilt, keep the soil acidic and regularly water the soil with a fungicide, such as carbendazim solution. Cut off the diseased leaves and spray the fungicide in time.
LACK OF NUTRITION
If the soil becomes alkaline, the leaves are also prone to yellowing. Do not keep watering tomatoes with tap water, but occasionally supplement with organic fertilizer water to help avoid leaf yellowing and allow the plant to grow strong.
When tomatoes are deficient in nitrogen, the old leaves at the bottom will yellow and the new leaves at the top will remain bright green, which is no big deal, as long as they are supplemented with some average or organic fertilizer in time to improve.
If tomatoes lack potassium, then the leaves of the whole plant will still be green, but their veins will turn yellow and the leaves will easily wither, so they need to be supplemented with potassium fertilizer in time.
Lack of calcium in tomatoes can lead to wilting of stems and leaves, the first manifestation of which is the yellowing and wilting of the tips of the stems and leaves and the rotting of the flowers after wilting, which is to be supplemented with calcium, which can be supplemented with bone meal or eggshell powder.
Tomato leaves yellow more common cause is a lack of magnesium, will lead to the outer edge of the leaves become pale white or yellow, the leaves are like dyed with a golden border, the veins of the leaves will also appear small yellow spots, you can timely supplement magnesium sulfate heptahydrate (laxative salt).
If the tomatoes lack sulfur, then the new leaves of the tomatoes will tend to yellow, but the old leaves can still maintain the bright green condition, the growth will become sluggish, and need to be supplemented with sulfur in a timely manner.
If there is a lack of zinc, then the area between the veins of the leaves will yellow, especially on new leaves that have just grown, and this condition will be more obvious.
All of the above tomato yellow leaves are relatively easy to improve, and can even be improved by being the fertility of the soil, the soil has more fertility, rich in humus, good drainage, then the tomato will grow strong, rarely will the leaves yellowing situation