High-Efficiency Multiple Cropping Technique for Winter Lettuce and Early Spring Peppers in Greenhouses
1. Select good varieties: For greenhouse cultivation of early spring lettuce, it is advisable to choose early-maturing pointed-leaf varieties with strong cold resistance, such as Hefei pointed-leaf duck-egg lettuce and Beijing crucian carp lettuce. 2. Grow strong seedlings: Sow and raise seedlings in a greenhouse in mid-to-late January. Before sowing, first soak the seeds in clean water at 20°C for 3-4 hours, rub and wash them, then remove and drain the water, and put them into...
Using greenhouses for multiple cropping of winter lettuce and early spring peppers can significantly improve the utilization rate of the greenhouse, increase cultivation yield and economic benefits.1. Cultivation of winter lettuce
1. Preferred variety: Choose the lettuce variety Shuiguasi, which is disease-resistant, high-yielding and cold-tolerant.
2. Careful seedling raising: Sow and raise seedlings in a small arch shed from late August to late September. After sowing, ventilate the greenhouse film from the bottom during the day and cover with a shade net to lower the temperature; on rainy nights, the greenhouse film must be properly covered. From pricking out to the seedling recovery stage, shading is needed during the day to create an ambient temperature suitable for lettuce growth. Control watering as much as possible, and do not water unless there is drought, to prevent the seedlings from growing excessively. Transplant into the greenhouse when the seedlings are 35 days old.
3. Fertilizer and water requirements: Apply 5000 kg of decomposed organic fertilizer and 50 kg of ternary compound fertilizer per mu as a base fertilizer, prepare the land and make beds, with a planting row spacing of 50 cm and plant spacing of 35 cm, planting about 3500 plants per mu. Water immediately after transplanting. During the seedling recovery period, ventilate when the greenhouse temperature exceeds 20°C, keep the daytime temperature inside the greenhouse no higher than 25°C and the nighttime temperature at 3-10°C. After the temperature drops, add grass curtains at night around the Beginning of Winter for insulation, and when the temperature is low, use double-film and double-covering insulation. In fertilizer management, adopt the method of lightly applying seedling-promoting fertilizer and heavily applying the spreading-stage fertilizer.
4. Disease control: Focus on controlling downy mildew, sclerotinia rot, soft rot and other diseases. Use 64% Sandofan at 500 times dilution to control downy mildew, 40% dimethachlon at 1000 times dilution to control sclerotinia rot, and 90% new streptomycin or 72% agricultural streptomycin at 1300 times dilution to control soft rot.
5. Timely harvesting: Harvest lettuce when it is neither too old nor too tender. If it is too tender or too old, the commercial value will be affected. Generally, it is more suitable to harvest when the edible rate of the fleshy part reaches more than 90%.
2. Cultivation of early spring peppers
1. Preferred variety: Choose the high-yielding, disease-resistant Haifeng 68 extra-large ox-horn pepper variety.
2. Careful seedling raising: Sow and raise seedlings in the greenhouse from late October to early November. During the seedling period, use double-film covering and add double-layer grass curtains for insulation. Prick out seedlings when the seedlings have 3 leaves and 1 heart, and transplant when flower buds appear, with a seedling age of about 100 days.
3. Transplanting management: After the lettuce is harvested, promptly prepare the land, apply fertilizer and make beds. Transplant in mid-to-early February when the greenhouse temperature stabilizes at 10-12°C, with a row spacing of 60 cm and plant spacing of 35 cm, planting 3000 plants per mu. After transplanting, water once to help the seedlings recover, and carry out intertillage 2-3 times; after seedling recovery, control growth. After the first pepper has set, apply 7.5 kg of urea and 4-6 kg of potassium sulfate per mu together with watering; during the full fruit stage, water lightly once every 7-10 days, and apply fertilizer with every other watering, each time applying 5-10 kg of urea and 8-10 kg of potassium sulfate per mu with the water; during the harvest period, apply 15-20 kg of diammonium phosphate as a top dressing together with watering. During the seedling recovery period, maintain the daytime temperature at 28-32°C and the nighttime temperature at 18-20°C; during the fruiting period, maintain it at 25-30°C during the day and 18-20°C at night. During plant growth, regulate the relative humidity to 50-70% by measures such as controlling watering and ventilation. Promptly remove side branches and old leaves below the first pepper, and promptly remove diseased leaves and old leaves in the middle and late stages of plant growth to facilitate ventilation and light penetration.
4. Disease control: The main diseases of peppers are phytophthora blight and brown spot. Use 25% Amistar at 1500 times dilution or 64% Sandofan at 500 times dilution, or Jinlei at 600 times dilution to control phytophthora blight, and use 77% Kocide at 1000 times dilution or 50% thiophanate-methyl at 600 times dilution to control brown spot.
5. Timely harvesting: Harvest the first pepper and the opposite pepper early to prevent the plant from being weighed down. Harvest promptly during the full fruit stage so as not to affect fruit setting on the upper part of the plant.