Lettuce cultivation techniques

Lettuce like cold environment, neither cold nor heat, suitable growth temperature is 15 °C ~ 20 °C, growth period 90 ~ 100 days. The open field is mainly cultivated in spring and autumn, and vegetable growers can sow in stages, followed by listing. March Sunlight greenhouse or Yangshuo nursery, seedling age 30 to 40 days, planting in early April, harvesting from early May to early June; open field nursery in late April to early May, planting in late May, harvesting in late June From the end of June to the end of July, seedlings will be planted in the open field from early July to early August and harvested from mid-August to late September.

One, selected broadcast variety

The growth pattern of lettuce on the leaves can be divided into lettuce and loose leaf lettuce (leaf lettuce is divided into wrinkled lettuce and erect lettuce). Lettuce lettuce: leaves full, serrated or deeply lobed, leaf surface smooth or shriveled, top leaves forming ball, rounded or rounded. Wrinkled lettuce: deep lobed leaves, loose or non-ballooning leaves; standing lettuce: leaves full or serrated, outer leaves narrow and long erect, non-balling or loose conical leaves. According to the need to select the appropriate species, such as glass lettuce, the emperor, Caesar, cabbage lettuce, mosaic lettuce, Great Lakes 659 and so on. 1 glass lettuce. The leaves are light green, wrinkled and shiny. Leaf margin wavy, middle ribs white, leaf group inward micro-holding, but not tight, easy to leaf blade, convenient dish, crisp and refreshing, slightly sweet, high quality. 2 Emperor. Referred to the United States, the leaves are green, the outer leaves are small, there are folds, and the edges of the leaves are cut off and the quality is excellent. Strong heat resistance, early maturity, suitable for early spring exposure and summer shade cultivation. 3 Caesar. Early maturing lettuce varieties imported from Japan. The plant is compact, neat and tidy, and the leaves are round, light yellow-green, heat-resistant, and have good ball-bearing performance.

Second, prepare the seedbed

Lettuce nursery should use water retention, fertility is good, fertile sandy loam. Bed soil preparation: 10 square meters of bed with maturity of 10 kg of organic fertilizer, ammonium sulfate 0.3 kg, 0.5 kg of superphosphate, potassium sulfate 0.2 kg, fully mixed evenly paved fine, pouring enough water, water seepage after sowing.

Third, planting seedlings

In order to spread the seed evenly, a small amount of fine sand can be mixed into the seeds during sowing. After sowing, it covers 0.3 to 0.5 cm thick fluvo-aquic soil and covers the film to moisturize. 30-50 grams of sowing per acre. When the seedlings begin to unearth, the mulching film shall be promptly removed to prevent leggy. The seedbed temperature is controlled at 18°C ​​to 20°C during the day and 12°C to 14°C at night. Pay attention to ventilation, in case of exposure to light, shading is required. When the seedlings grow to 2 to 3 true leaves, the seedlings are planted at a spacing of 6 to 8 centimeters and grow to 4 to 5 true leaves. The seedlings usually do not lack water and do not pour. For the prevention of seedling disease, spray 1 to 2 600 times 75% of chlorothalonil solution.

Fourth, scientific fertilization

Lettuce requires rich organic matter, water retention and strong fertility of the clay loam, lettuce slightly acidic, the soil pH value of 5 ~ 7 is appropriate. For every 1,000 kilograms of lettuce produced, 2.5 kilograms of nitrogen, 1.2 kilograms of phosphorus, and 4.5 kilograms of potassium need to be absorbed. Knotted lettuce requires more potassium. The growth phase requires the use of nitrogen, phosphorus, and potassium fertilizers. The plots for planting lettuce are to be ploughed deeply and the base fertilizer should be applied before the planting. The Mushi rotted farmyard manure 3000 to 3500 kg, deep-cast after application, and poured enough water to see if it is dry.

V. Careful planting

The seedlings were irrigated the day before planting to make the seedlings moist, and the seedlings were raised as much as possible on the second day to reduce root damage. When planting, first ditch the surface, ditch depth of 4 to 6 cm, 70 cm planted three rows of plants, after the ditch 25 kg per mu after the application of compound fertilizer after irrigation, water infiltration by the spacing of 24 cm Miao Pei soil seal ditch, will be flattened, cover the film, seedling film.

Sixth, management after planting

Lettuce and lettuce are wet, and sufficient water supply is required throughout the growing period. Planting 5 to 7 days after pouring 1 time Huanmiao water. After irrigating the seedlings, the mulching plots were used for 2 times of cultivating tillage weeding. After pouring 3 to 4 times of water, combined with watering period topdressing nitrogen and phosphate fertilizer, Mushi 15 to 20 kg. Stop watering before harvest to facilitate storage and transportation.

Seven, scientific harvest

Non-butter lettuce can be harvested by the camera based on market prices. After the lettuce is harvested, it is better to harvest the leaves closely. If it is too early, it will affect the yield. If it is too late, the inner stems of the leaves will elongate and the quality of the leaves will become loose.

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