This period is a suitable temperature, generally between 10℃ and 20℃, which is suitable for the growth of lettuce. At the same time, abundant sunshine and moderate rainfall in autumn are beneficial to the growth and development of lettuce. Therefore, during this period, open-air seedling raising can provide a good growth environment for lettuce, which is beneficial to the growth and development of lettuce.
In the process of overwintering lettuce seedlings in the open air, we need to pay attention to the following points. First, choose a good nursery. Lettuce likes sunny and well-drained soil, so when choosing a nursery, try to choose a place with sunny, loose soil and good drainage.
Secondly, carry out proper fertilization. In the process of lettuce growth, proper fertilization can provide sufficient nutrition, which is beneficial to the growth and development of lettuce. However, attention should be paid to controlling the amount of fertilization to prevent lettuce from growing too fast due to excessive fertilization. In addition, pay attention to watering in time to keep the soil moist, but avoid water accumulation.
Finally, pay attention to cold and warmth. Lettuce overwintering in the open air is easily affected by low temperature, so it should be covered and protected in time before the arrival of low temperature weather to prevent lettuce from freezing.
Sowing method:
Lettuce is sown on cloudy days in summer. Sow wet seeds to cover the film in the first half of April-May, and remove it after emergence. From the end of May to the beginning of July, cover the sun-shading net with a small arch shed or flat shed until seedlings emerge or two real leaves appear. Cover with sunshade net in rainy days to prevent rain from washing away. 10 square meter is used for sowing 5- 10 gram. The seedling spacing before 2 true leaves is 1 time, the time between 4-5 true leaves is 1 time, and the seedling spacing is 10 cm.
Healthy seedlings can also be planted at high density according to the row spacing of 10 cm. After each plant spacing, seedling fixing and transplanting, cooperate with watering and apply decomposed dilute manure. Clear ditches and drain water stains in rainy days, and water 0.50% urea solution 1 time about 5 days before planting. About 25 days after seedling formation or transplanting, the seedlings can be harvested one after another and put on the market.
Wet the seedbed thoroughly before sowing autumn lettuce. After sowing, cover with 1 layer of 3-40% decomposed pig manure residue and 1 layer of fine straw, or cover with black sunshade net, and sow germinated seeds or wet seeds. Before emergence, cover the seedbed soil with a double floating surface, and after emergence, cover it with a silver-gray sunshade net. Water and fertilize in the morning and evening, keep the bed soil moist and weed in time.
Baidu encyclopedia-lettuce