9 REASONS WHY YOUR TOMATO LEAVES ARE TURNING YELLOW AND HOW TO FIX IT.
9 reasons why your tomato leaves are turning yellow and how to fix it.
There are many reasons why tomato plant leaves can turn yellow. Yellow leaves can be a sign of a deeper problem in the plant, from lack of sunlight to the presence of viruses. Diet, disease, and environment can all be to blame for why leaves turn yellow on any plant, including tomatoes.
Why are my tomato leaves turning yellow?
Diagnosing and correcting the problem is important for the health of the tomato plant and its fruit production. We will explore 8 reasons why tomato turns yellow and help you find a way to solve the problem.
1. Transplant shock
A few yellow leaves a week or two after tomato plants are transplanted into the garden is common. After spending a few weeks growing in the changing environment of the greenhouse, the growing plant is exposed to changing temperatures, wind and humidity. A few yellow leaves is not usual.
What to do:
Give plenty of water. Seedlings grow in soil, but not wet. They will establish a large root system in about four weeks. At that time, switch to deep water plants once or twice a week during the dry season. Also limit seedling stress by protecting young plants from cold temperatures. If the night temperature falls below 45 °F, cover the plant with a bucket or box.
2. lack of Nutrient
Tomato plants grow quickly and this growth requires a lot of nutrient. When the necessary nutrients are not available and the tomato plant grows quickly, yellow leaves may develop. A common nutrient deficiency is nitrogen, which often causes older leaves to turn yellow as plants release nitrogen from them to encourage new growth. Iron can also be scarce. A sign of iron deficiency is yellow leaves growing on healthy plants. Low magnesium levels are a problem in some soils. Plants without magnesium show yellow spots on old leaves.
What to do:
Only fertilize tomato plants with an all-purpose vegetable fertilizer. Follow the instructions on the packaging exactly.
3.Early Blight
This frustrating fungal disease first appears on the young leaves of the plant. Small brown lesions develop on the surrounding tissue that soon turn yellow. Downy mildew lives in the soil and spreads on leaves when it rains or when plants are planted.
What to do:
Remove leaves and stems from diseased tomatoes and discard them. Clean pruned plants between cuts to reduce the chance of spreading disease. Prevention is the key to avoiding disease in time. Alternate planting of the tomato family (peppers, eggplants and potatoes) in three years to avoid mildew on the ground. Mulch the tree so that it does not spray the leaves and deliver water directly to the base of the tree using a water lance or a water dropper; do not water the surface.
4. Late Blight
Especially in a cool, humid climate, early heat causes the young leaves on the tomato plant to turn yellow. Yellow leaves cover brown spots. Expect the leaf to turn brown quickly and fall off the tree. Spread by wind and rain, mildew can spread quickly through fields or areas.
What to do:
Remove and destroy infected plants as soon as they are found. Prevent early disease by planting seedlings 3 to 4 feet apart to promote good air circulation. This will help the foliage to dry faster and can prevent mildew from taking hold. Avoid surface water; instead, use a watering wand or dripper to direct water to the root zone of your tomato plants.
5. powdery mildew
Powdery mildew is a leaf disease that causes yellow spots on the leaves of the plant at any time during development, but it is more common when tomatoes are growing. Examine the paper carefully and you will see a white powdery color on the top and bottom of the leaves.
What to do:
Fungicides containing sulfur or copper can be effective. Organic products are also effective. Look for products that contain sesame, rosemary, or thyme botanical oils or potassium bicarbonate as active ingredients. Fungicides should be applied weekly to maintain control.
6. Fusarium wilt
What usually happens when tomatoes begin to ripen, Fusarium wilt causes the leaves in the lower half of the plant to turn yellow. Sometimes, only one part of the plant will have yellow leaves. The yellow leaves will soon disappear and the whole plant will eventually die. Fusarium wilt is caused by a fungus in the soil.
What to do:
Remove and destroy infected plants. The best protection against Fusarium wilt is to plant resistant tomato varieties. ‘Solar fire’, ‘Top Gun’ and ‘Mountain Merit’ all have some resistance to Fusarium wilt.
7. Salt damage
Tomatoes grown in containers are prone to developing excess salts or minerals in the soil. A lot of salt and minerals from the water build up in the soil, depriving the plant of useful nutrients and causing the leaves to turn yellow.
What to do:
Once a week, water the bag until the water comes out of the bottom of the bag. This will remove excess salt and minerals. Washing will also wash away the beneficial nutrients, so make sure you are fertilize the growing tomatoes in the container regularly.
8. Herbicide damage
Tomatoes are sensitive to herbicides, even small amounts can escape from nearby applications. Leaves affected by herbicides quickly turn yellow, possibly white, from the inside of the leaf to the edges.
What to do:
There is no cure for tomatoes affected by this weed killer. The best way is prevention. Do not use herbicides near tomatoes; Remember that volatile compounds can travel long distances in the air and affect plants that are far from the water source.
9. Too much or not enough water
Tomatoes usually need about 1 to 2 inches of water per week. Plants that grow in fast-draining sandy soils need more water each week, while plants that grow in slow-draining loam or clay soils grow best with 1 inch of water. . Too much or too little water can cause the leaves to turn yellow.