Growing tomatoes is easy and rewarding for beginners and for seasoned gardeners as well because you get to enjoy the fruit of your hard work in the form of fresh and organic tomatoes. There are many varieties with distinct colors, textures, and flavors you can try every year without getting bored. However, it’s so unfortunate that tomatoes are not immune to infectious diseases. You might come across tomato leaves turning brown and wonder about the reason behind it. There could be multiple reasons behind it, and in this article, we have discussed it in detail to help you identify the cause. We have discussed the reasons for tomato leaves turning brown.
Infestation With Spider Mites
The common symptoms of spider mite infestation are brown specks with webbing on tomatoes. They suck sap from the leaves, leaving it nutrient deficient, which results in brown or yellow leaves, which may lead to plant death if it is not treated on time.
| Tips to Avoid Spider Mite Infestation : Water the plant properly because tomato plants thrive in moist conditions, and spider mites hate moisture. Neem oil or insecticidal soaps will also do the job of keeping spider mites away. |
Bacterial Disease
Bacterial disease spread from leaves to the entire tomato plant within no time. Xanthomonas bacteria cause brown spots on the plant leaves, which eventually affect the fruit.
| Tips to Avoid Bacterial Disease : Prevention is better than cure, so dispose of the plant with bacterial leaf spot disease, try planting tomatoes where water moves towards the roots, use healthy seeds, and never water from overhead. |
Verticillium Wilt
This is a dangerous fungal disease that leads to brown leaves on tomato plants due to soil-borne fungus that spreads to other neighboring plants as well if not taken care of immediately. Verticillium wilt first turns the lower part of leaves brown, then spreads to the stems, making them frail, and finally spreading to the entire plant, causing harm.
| Tips to Control Verticillium Wilt : Try to plant a verticillium-resistant variant of tomatoes, and make sure the roots get enough air to prevent root rot and fungus. |
Underwatering the Plant
Plants need sufficient water to grow properly. If you don’t water them regularly, crispy brown edges start to develop around the leaves showing sign of water requirement.
| Tips to Care : Water at the plant’s root because tomato roots run deep so kindly ensure that they receive enough water, avoid overhead watering because roots won’t get water through overhead watering, and avoid splashing water during overhead watering to prevent disease. |
Late Blight
Late blight is a fungal disease that can be prevented if you uproot and destroy the crop with symptoms of late blight. The late blight can be identified with a light green spot that turns into a dark brown color with a light and fuzzy mold appearance. The disease is also seen on the stems, making the veins deficient in nutrition.
| Tips to Prevent Late Blight : Water the plant regularly, sow disease-resistant plants, mulch around the plant’s base, and maintain good hygiene. |
Early Blight (Fungal Disease)
If you identify the symptoms early and start the treatment, early blight disease can be avoided. This is an air-borne fungal disease that causes spots on the leaves of approximately half an inch, which eventually darkens.
| Tips to Prevent Early Blight : Prevention strategy is the best way to keep plants healthy. Remove the infected leaf as soon as possible so that it doesn’t spread to another part of the plant. |
Bacterial Disease “Canker”
Usually, leaves turn brown when infested with canker. The other symptoms are brittle brown edges of the leaf, which spread to the tomato fruit as well.
| Tips to Care : Water them properly and use healthy seeds. |
Lack of Hygiene
A healthy environment is essential for robust growth of tomato plants. If you have taken all the preventive measures and yet some leaves turn brown. Then the reason can be narrowed down to hygiene. Create a proper, healthy environment for plants to grow well.
| Tips to Care : Keep the plant area free from weeds, dust, and dirt. |
Nutrition Deficiency
Tomato plants require an ample amount of nutrition, so the plant utilizes the available nutrients quickly, leaving the leaves brown and dull.
| Tips to Care : Fertilize the plants every fourteen days with liquid fertilizer for strong and healthy growth. |
Root Knot Nematode
The affected plants appear wilted, and the roots, when dug, have round galls caused by microscopic nematode worms that affect root functioning.
Herbicide Injury
Another reason for brown leaves is herbicide injury, which happens when the wind blows the herbicide away from the target plant to the tomato plant.
| Tips to Care : When the wind is not blowing, apply liquid dandelion killers and keep granular applicators away. |
