Hydroponic lettuce can be planted directly. Prepare sponge, cut it into small squares and clean it. Select seeds with full and undamaged seeds, dry them in the sun, soak them in copper sulfate solution, take them out and wash them, and soak them in warm water at 45℃. The soaked seeds are directly planted on the sponge and soaked in water to promote germination. After the growth is stable, the hydroponic container is prepared and the seedlings are hydroponically planted.

First, prepare a sponge.

Hydroponic lettuce can be planted directly. First, prepare a loose sponge, about 3 cm thick, cut the sponge into small squares and put it in water to clean it.

Second, prepare seeds.

There are many varieties of lettuce. You can determine the variety of lettuce according to your own preferences and local conditions, and choose seeds with good appearance, full seeds and no damage. Good quality seeds can improve the germination rate. Rinse the seeds with clear water and then dry them in the sun to remove excess water from the seeds. Soak the seeds in copper sulfate solution, take them out and wash them, and then soak them in warm water at 45℃ to promote the seeds to fully absorb water.

Third, sow.

The soaked seeds are directly planted on sponges, each sponge is planted with 2-3 seeds, and then water is added to soak the sponges, waiting for the seeds to germinate.

Fourthly, seedling management.

After sowing, put it in a cool and ventilated place, spray water to keep moisture, and avoid direct sunlight. About the tenth day after sowing, the true leaves will spread out, and nutrient solution can be sprayed at this time.

Five, hydroponic planting

After the seedlings grow stably, the hydroponic container can be prepared for hydroponic planting. During the first 10 day after planting, the indoor temperature should be kept at about 25-28 degrees Celsius, water should be changed regularly to keep the water clean, and potassium dihydrogen phosphate should be sprayed to supplement nutrition.