Why Newly Planted Tomato Seedlings Keep Wilting and How to Fix It

Fellow tomato growers, it is truly frustrating when tomato seedlings suddenly wilt! Don't panic. Today we will help you analyze the causes of tomato seedling wilting and treat the root of the problem.

1. Temperature

High temperature

In summer, under strong sunlight or after a long cloudy spell suddenly turning clear, tomato seedling leaves easily curl into tubes and turn dark green. This is the work of high temperature and drought. High temperature makes soil moisture evaporate quickly, leaving the plant short of water.

Solution: Shade with a shade net from 11:00 to 15:00, avoid spraying water at midday heat to cool down, and water slowly with small amounts to keep the soil moist.

Low temperature

In early spring or autumn and winter, new leaves curl and turn purple while old leaves bend downward. This is caused by low-temperature chilling injury. Low temperature affects cell activity and the root system's nutrient uptake.

Solution: Cover with plastic film or build a small arched shed to keep warm, keep nighttime temperature above 12°C, and spray 1:2000 brassinolide to enhance stress resistance.

2. Water and Fertilizer

Watering

After transplanting, if water is controlled too much, the roots float on the surface and the plant easily wilts in high heat.

Solution: Water thoroughly right after transplanting to settle the roots, then control water reasonably after the seedlings recover, and avoid flood irrigation.

Fertilizing

Excess nitrogen fertilizer makes leaves thick, dark green, and curled; a lack of potassium and calcium causes leaf edges to scorch and curl upward, and may also cause blossom-end rot.

Solution: Pause nitrogen fertilizer, spray 1:800 monopotassium phosphate or 1:1500 chelated calcium, and apply wood ash or gypsum powder to the soil to supplement potassium and calcium.

3. Pests and Diseases

Root diseases

Root rot and fusarium wilt cause the roots to turn brown and rot, and wilting becomes worse after watering.

Solution: Drench with metalaxyl-fludioxonil plus Bacillus subtilis, and rotate with legume plants.

Viral disease

Leaves yellow, curl, and crinkle, and the plant becomes stunted. It is spread by aphids and whiteflies.

Solution: Pull up diseased plants and destroy them, spray ningnanmycin plus zinc fertilizer to suppress the virus, and hang yellow sticky boards to trap and kill aphids.

4. Other Points to Note

Fine feeder roots damaged by high temperature or high fertilizer concentration should be dug out and dried, then replanted in dry soil. Plants infected with root rot should be removed promptly, and sterilization agents such as thiram and carbendazim should be mixed into the soil in advance for prevention.

Generally, after adjusting according to these methods for 1-2 weeks, leaf curling and wilting symptoms will ease. If symptoms persist or worsen, you need to check whether multiple factors are overlapping, and if necessary switch to disease-resistant varieties such as those resistant to TY virus.