Tomatoes are very appealing to grow in a garden or a greenhouse. However, there are tomato troubles you have to be aware of. For example, while checking your plants in the morning you can find out that someone ate your tomatoes at night!
There are many reason why tomato plant leaves are turning yellow. However, if you notice that tomato leaves are tuning yellow and identify the reason why early, it is easy to fix this problem.
What makes tomato plant leaves yellow?
Reason 1 – It is absolutely normal for mature plants. A few lower leaves on a mature tomato plant can turn yellow sometimes, dry out and fall eventually.
Reason 2 – Underwatering causes yellow leaves on tomato plants. If the leaves look dry and are crunchy when you touch them, you need to water them more.
It doesn’t necessarily mean that you are not watering your plants enough, it might be due to poor drainage. The soil should be well-drained. Sometimes when you are watering the plants water might not be reaching the roots resulting in the waterlogging of the plants.
If underwatering and waterlogging are present, you need to improve the soil drainage. Start using sand or planting in raised beds, also, you can use compost or transplant mix.
Reason 3 – Overwatering is the most common reason why tomato plant leaves are turning yellow. If the leaves are yellow and limp, it means that you water your plants too much.
If you noticed yellow leaves on the plant, check the soil first – is it dry or soaked? Water tomato plants the most when transplanting them into the garden as well as when they are very young seedlings.
Soak tomato plants once every 5 to 7 days. Let the soil dry before watering and make sure the soil is not left soggy. It is important to water tomato plants at the base of the plant and avoid the leaves. The best time of the day to water tomatoes is early in the morning.
On the hot days you need to water your tomato plants once a day. Make sure to have one deep watering daily. It is also applicable to the plants that are bearing fruit.
Reason 3 – The cause for yellow leaves can be the lime compost. If upper leaves of tomato plant are firm and yellow it can be due to lime added to the compost. Also, if you use hard water on lime-hating plants, it can yellow leaves. Opt for lime-free compost to solve this problem.
Reason 4 – Cold droughts lead to leaves turning yellow. If you noticed that several tomato plant leaves turn yellow simultaneously and the fall, it is likely due to cold droughts.
Reason 5 – Yellow spots or patches on the leaves are signs of the viral infection. The plant could be bought already contaminated with infection. Alternatively, the viral infection was carried to the plant by an insect. Unfortunately, you can’t cure viral infections. However, you can get rid of the tomato bugs to prevent them from spreading viruses.
Reason 6 – Lack of sunlight on mature plants leads to bottom tomato plant leaves turning yellow. When the plant matures it becomes bushy and the top leaves can block the bottom leaves getting sunlight. This often leads to yellow leaves but it is totally normal.
Reason 7 – Nutrients deficiency results in yellowing. It is also known as chlorosis. Leaves don’t produce enough chlorophyll which is responsible for the green color of the leaves.
Chlorotic leaves are usually pale, yellow or yellow-white. Lack of nutrients in the soil means that plants don’t get enough nutrients to synthesize chlorophyll. As a result, leaves are turning yellow.
The most common nutrient deficiencies in plants are iron, nitrogen, magnesium and zinc. The type of yellowing helps to determine what nutrients the plant is lacking. For example, if areas between the veins of the youngest leaves turn yellow, that is the sign of iron deficiency.
Why are my tomato plants turning yellow on top?
If you noticed that tomato plants are turning yellow on top, that is most likely due to tomato diseases or pests present in or around the plants. For example, infection with Ringtop virus can cause leaves yellowing to be spreading upward. In addition, if yellow leaves are curling up as well, it can be caused by a tomato yellow leaf curl virus.
Why are tomato plant leaves turning yellow and purple?
There are 4 main reasons why tomato plants leaves are turning yellow and purple:
- Temperature fluctuations – Tomato plants require warm temperature (at least 50° F) and planting in a cold greenhouse will lead to young plant leaves turning purple.
- Phosphorus deficiency – it is the most common reason why veins of tomato plant leaves are turning purple or the whole leaf turns purple.
- Infection with leaf curl virus – the symptoms can differ by plant but most of the time tomato plant leaves are curling, the leaf veins are becoming purple and the leaves are turning yellow.
- Infestation with psyllid pests – the affected tomato plant leaves are turning yellow and the veins purple along with the upright appearance to the leaves as a result of the disease known as psyllid yellows.
Why are tomato plant leaves turning yellow and curling?
There are two reasons why tomato plant leaves are turning yellow and curling: underwatering and viral diseases. Crispy to touch yellow leaves with a slight curl are a sign of watering problems. On the other hand, a geminivirus known as a tomato yellow leaf curl virus transmitted by whiteflies causes tomato leaves to turn yellow and to curl upwards.
Why are tomato plant leaves turning yellow and brown?
It is most likely that tomato plant leaves are turning yellow and then brown because the nutrient deficiency got more severe. Generally, if you notice that the leaves have yellow or brown spots, test the soil to find out which nutrient the plant is missing.
Should I remove yellow leaves from tomato plant?
You should remove yellow leaves from tomato plants to prevent them from becoming a sugar drain on the rest of the plant. Also, removing yellow, dry leaves helps to increase the fruit production. Remember that dead plant material on the soil promotes mold development.
Can yellow leaves turn green again?
Will yellow leaves turn green again depends on the reason why leaves turned yellow. If it was due to nutrients deficiency and you fixed it right away, there is a high chance that yellow leaves might turn green again.
However, if it is a mature plant and leaves are old, yellowing is just a stage before falling off. Generally, it is better to remove leaves which are half way yellow as these can’t turn green again. Crispy and necrotic plant tissue is, unfortunately, not able to recover.
