Causes and Control Methods of Leggy Cucumber Seedlings

During the cucumber seedling-raising process, after the seedlings emerge, attention should be paid to hardening the seedlings; the seedbed needs to maintain humidity, watering should not be excessive, and ventilation conditions should also be strengthened to prevent the seedlings from growing excessively and forming leggy seedlings. So how should leggy cucumber seedlings be controlled? Follow the editor to take a look.

1. Symptoms

Leggy seedlings have large leaves, thin leaves, a lighter color, and thin, long stems with large internode spacing. If the root system is dug up, the roots will be found to be short and small, with little dry matter accumulation. Because the root system is weak, its ability to absorb fertilizer and water is weak; the stems and leaves are tender, and the cuticle on the surface is not well developed. Once air humidity decreases, transpiration intensifies, and at this time the leaves will wilt. Leggy seedlings have poor stress resistance and are highly susceptible to freezing and disease infection. Because of nutritional deficiency, leggy seedlings form flower buds more slowly, with fewer and later flowers, often forming deformed fruit, prone to flower drop, and low yield.

2. Causes

The main causes of leggy seedling formation are nighttime temperature being too low, a small day-night temperature difference, insufficient light, poor ventilation, excessive water, excessive application of nitrogen fertilizer, and too little application of phosphorus and potassium fertilizer. When the seedlings have just emerged, because ventilation conditions are poor and ventilation is not carried out in time, contact with the covering material will cause the seedlings to grow excessively; at this time the seedlings are relatively sensitive to temperature, and under high-temperature conditions the hypocotyl is very likely to elongate. Another cause is that before planting, the outside temperature gradually rises and the weather turns warmer, so the seedlings grow faster; at this time the plants crowd each other and shade each other from light, resulting in leggy seedlings.

3. Control Methods

First, when building the seedbed, the proportion of nutrient soil should be reasonable. It can be prepared by mixing organic fertilizer and garden soil. The organic fertilizer must be fully decomposed, and the garden soil must not be chosen from land where cucurbit vegetables have been planted, so as to avoid infection by pests and diseases, and it should also be sieved. After the seedlings emerge, the humidity and nighttime temperature of the seedbed should be controlled; generally, keep it between 15-20 degrees in the first half of the night, keep it at 10-15 degrees in the second half of the night, and it must not be lower than 5 degrees in the morning, maintaining a certain day-night temperature difference. When the seedlings show excessive growth, they can be sprayed with a 2500-3000 times dilution of 50% chlormequat. After 10 days of spraying, the seedlings will be found to grow slowly, the leaf color will become darker green, and the stems will become sturdy.

  The above is an introduction to the causes and control methods of leggy cucumber seedlings. We hope it can help you. If you want to learn more related knowledge, please follow us.