Why Tomato Leaves Turn Yellow and Wither, and How to Treat Them with Medication

Have you ever come across yellowing, wilting leaves when growing tomatoes? Actually, yellowing and wilting leaves are not caused by a single reason. Today I will talk about the causes and how to remedy them.

Nutrient Deficiency

Symptoms: leaves turn yellow and growth slows down, and different nutrient deficiencies show different signs

Nitrogen deficiency: older leaves turn yellow first, and the whole plant is short and spindly.

Iron deficiency: new leaves turn yellow while the veins remain green.

Magnesium deficiency: leaf edges turn yellow, and yellow mottling appears between the veins.

Remedy: choose the corresponding fertilizer according to the type of deficiency! For nitrogen deficiency, use urea or well-rotted organic fertilizer; for iron deficiency, supplement with ferrous sulfate solution (diluted and watered onto the roots or sprayed); for magnesium deficiency, use magnesium sulfate, diluted to a 0.2%-0.4% solution and sprayed on the leaves, once a week for 1 time, for 2-3 times in a row!

Disease Infection

Symptoms: spots and mold layers appear on the leaves, which gradually wither and turn yellow

Remedy: once diseased leaves are found, remove and destroy them immediately! Avoid spreading the infection! For leaf mold, use fungicides such as carbendazim and thiophanate-methyl, diluted and sprayed; for viral diseases, use ningnanmycin, sprayed at the ratio stated in the instructions, once every 7-10 days, and at the same time pay attention to controlling the insects that spread the virus!

Pest Infestation

Symptoms: leaves have insect holes and spots, and insects or eggs can be seen on the undersides of the leaves

Remedy: when only a few pests are found, rinse the undersides of the leaves with clean water or soapy water to wash away the insects and eggs! When the infestation is severe, hang yellow sticky traps, or use insecticides such as imidacloprid and abamectin, remembering to dilute them at the correct ratio and avoid spraying during the hottest part of the day!

Environmental Problems

Symptoms: the plant looks poor overall, with yellowing leaves

Remedy: tomatoes are light-loving plants, so make sure they get at least 6-8 hours of light a day! For indoor growing, place them on a south-facing balcony, or use a grow light! Keep the temperature at 20-30°C, provide some shade during the summer heat, and move them somewhere warm when the temperature drops below 10°C.

Potting Soil Problems

Symptoms: water collects after watering, and the soil becomes compacted and hard

Remedy: simply change the soil and choose a loose, airy, organic-rich potting mix, such as leaf mold+peat moss+perlite1:1:1 mixed together, and trim off any rotten roots when repotting! Loosen the soil regularly, avoid giving "half-water", and water once a month with diluted white vinegar water to adjust the soil pH.

Everyday care tips: water only when the soil is dry and water thoroughly, avoiding waterlogged soil and root rot; fertilize regularly, with light, frequent feedings; keep good air circulation to reduce the buildup of pests and diseases.

I hope everyone's tomatoes grow healthy and are loaded with bright red fruit!