Lettuce cultivation techniques

1, climatic conditions

Lettuce like a cool climate, the minimum temperature for seed germination is 4 °C, longer time. The optimum temperature for germination is 15 to 20°C, germination for 3 to 4 days, and germination at 30°C or more. Therefore, during the summer sowing, low temperature treatment is required to promote enzyme activity and other transformation of the seeds. The optimum temperature for the growth of stems and leaves of lettuce was 11-18°C, and the suitable temperature for the ball stage was 17-18°C. Seedlings can tolerate low temperatures of -5°C. Above 21°C, it is not easy to form leaf ball or the internal temperature of the leaf ball is too high, which causes the heart leaf to rot and rot. At temperatures above 30°C, poor growth occurs. The non-heading lettuce has a wider temperature adaptation range than the lettuce. Sensitivity to sunshine response was the most sensitive in early maturing varieties, followed by mid-maturing varieties, and late in response to late-maturing varieties.

2. Soil conditions

Lettuce suitable for slightly acidic soil, planted in organic soil rich in fertility, water conservation, strong fertility, high yield, such as the planting in arid and dry soil, root development is not complete, growth is not full, slightly bitter taste of the dish, poor quality.

3, moisture conditions

Lettuce different growth period, different requirements for water, seedlings can not be dry not too wet, too dry seedlings easy to aging, too wet seedlings easy to grow. Hair growth period, to properly control the water, the ball period of water should be sufficient, lack of water leaves, bitter taste. Do not add too much water to the late ball to prevent the occurrence of fissuring and cause disease.

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