Soilless cultivation techniques of lettuce

First of all, we should select the right variety, then accelerate the germination of the seed, and sow the seed when the seed is white. The seeds can be sowed directly in the planting cup, sowing 1-2 seeds in each cup, covering a layer of matrix after sowing, drenching enough water and waiting for seedlings to emerge. When the seedling has 6-7 true leaves, it can be planted, and the nutrient solution and temperature management can be done after planting.

1. Variety

The varieties of lettuce used in soilless cultivation are soft-tailed lettuce, Italian lettuce, emperor, great lake 366, big lake 118, crisp, Martha, mini lettuce and so on.

2. Sprouting

Soak the seeds in 20 degrees water for 3 to 4 hours, scrub and drain, place on clean and moist gauze and germinate at 15 to 20 degrees. Generally, after 2-3 days, the seeds can be exposed and sown at this time.

3. Sowing seeds

The seeds were sown directly in a planting cup filled with fixtures such as vermiculite or in a seedling plate filled with seedling substrate. 1-2 seeds were sown in each cup and covered with a layer of substrate after sowing. Then cover it with a sunshade net, drench it with clean water, keep it moist, and wait for seedlings to emerge.

4. Colonization

The suitable planting period is when the seedlings have 6-7 true leaves. About 10 days before planting, the moisture should be properly controlled according to the seedling condition. when planting the seedlings, the seedlings should first stand in the center of the nutrition bowl, and then fill the seedlings with vermiculite.

5. Nutrient solution

The nutrient solution formula adopts lettuce special formula or leaf lettuce general formula. The nutrient solution formula suitable for lettuce growth is (g / t): calcium nitrate 621, potassium nitrate 444, potassium dihydrogen phosphate 330, magnesium sulfate 500, ammonium nitrate 69. Or adopt Japanese garden test formula: calcium nitrate 945, potassium nitrate 809, potassium dichlorophosphate 153, magnesium sulfate 493. The concentration, pH, depth and nutritional supplement of the nutrient solution will change during the growth period.

6. Temperature

Lettuce likes cold climate, and the suitable temperature for growth is 15-20 ℃. It is most suitable to grow in the environment with large temperature difference between day and night and low temperature at night. The daytime temperature can be maintained at 18-20 ℃, the air temperature should be kept at over 25 ℃, and the night temperature should be kept at 10-12 ℃.