TheNaturePlanet

For many growers, tomato seedlings suddenly wilting can be frustrating. Don’t worry—here are the most common causes and practical fixes to help your plants recover.

1. Temperature Stress
High temperatures: In hot summer weather or after long cloudy days followed by sudden sun, leaves may roll into tubes and turn dark green due to heat and drought stress.
Solution: Provide shade between 11:00 a.m. and 3:00 p.m., mist to cool down, and water lightly and frequently to keep the soil moist.

Low temperatures: In early spring or autumn/winter, new leaves may curl and turn purple, while older leaves droop. This is cold damage.
Solution: Use plastic mulch or small tunnels for insulation, keep night temperatures above 12 °C (54 °F), and spray brassinolide to boost stress resistance.

2. Water and Fertilizer Management
Improper watering: If water is restricted too much after transplanting, roots may stay shallow, making seedlings wilt under heat.
Solution: Water thoroughly after transplanting, then adjust watering moderately; avoid flooding.

Nutrient imbalance: Excess nitrogen makes leaves thick, dark green, and curled; potassium or calcium deficiency causes leaf-edge scorch, upward curling, and blossom-end rot.
Solution: Stop nitrogen application, spray potassium dihydrogen phosphate or chelated calcium, and apply wood ash or gypsum to the soil.

3. Diseases and Pests
Root diseases: Root rot and fusarium wilt cause root browning and decay, with wilting worsening after irrigation.
Solution: Drench with fungicides such as metalaxyl + fludioxonil, combined with Bacillus subtilis, and practice crop rotation.

Viral diseases: Symptoms include yellowing, curling, and crinkled leaves with stunted growth, often spread by aphids or whiteflies.
Solution: Remove and destroy infected plants, spray ningnanmycin plus zinc fertilizer, and use yellow sticky traps for aphid control.

4. Other Notes
High temperatures or overly concentrated fertilizers can burn fine roots. Replant into dry soil if necessary.

Remove plants with severe root rot promptly and disinfect soil in advance with fungicides such as carbendazim.

In most cases, symptoms improve within 1–2 weeks with proper adjustments. If wilting continues or worsens, multiple factors may be involved. In such cases, consider switching to disease-resistant tomato varieties.