Detailed Explanation of Key Technical Points for Efficient Ginger-Scallion Rotation Cultivation

Ginger has a distinctive spicy flavor due to compounds such as gingerol, zingerone and gingerol alcohols, and is a seasoning vegetable commonly used by people; annual sales nationwide now exceed 400,000 t, and export momentum is strong. Welsh onion (Allium fistulosum) is even a ton-scale vegetable exported from China to Japan, so research on efficient cultivation techniques for these two vegetables is of great practical significance. Through years of exploration and research, we have developed a set of efficient rotation techniques.

1 Early-maturing cultivation techniques for greenhouse ginger (previous crop)

1.1 Variety selection

Shandong Large-leaf Ginger (Shandong Yellow Ginger, Shandong Large Ginger). Purchase seed ginger one week before Frost's Descent each year, and carry out smoke-ginger germination promotion around the 20th day of the twelfth lunar month. Before germination promotion, carefully select ginger pieces that are plump, flat in shape, glossy, not shriveled, not frost-damaged, free of wounds and pests and diseases, and conform to the variety's characteristics. Before germination promotion, sun-dry the selected seed ginger on a sunny day; stop sun-drying when the ginger flesh becomes dry, whitish and slightly wrinkled. Sun-drying helps reduce the moisture content of seed ginger and raise its temperature, favoring uniform sprouting. About 1000 kg of seed ginger is used per 667 sq m of field.

1.2 Smoke-ginger germination promotion

For germination promotion, a smoke-ginger house is generally used, with bamboo beds built at a height of 80 cm; seed ginger is placed on the beds, and charcoal is used beneath the beds for heating. The temperature is controlled at about 25°C, and germination promotion lasts 35-40 days. Keep only 1-2 strong shoots per piece, and remove excess ginger shoots at the same time.

1.3 Land preparation and basal fertilizer application

Ginger has a weak root system, is afraid of both drought and waterlogging, and avoids continuous cropping. The cultivation site should be selected as sandy loam soil with slightly higher terrain, convenient drainage and irrigation, and deep, loose, fertile soil. If conditions permit, it is best to deeply plow the soil before winter, expose it to whiten, and let it weather. For greenhouse cultivation, 30 days before planting, build a moso bamboo greenhouse 6-8 m wide and cover it with film, and deeply plow the soil once to raise ground temperature and reduce soil moisture content, while digging drainage ditches between greenhouses. In early February, apply 4000 kg of decomposed pig manure, 50 kg of potassium sulfate three-element compound fertilizer, and 50 kg of superphosphate per 667 sq m as basal fertilizer.

1.4 Planting density and method

The planting period is selected in mid-February, and beds are made before planting, 150 cm wide, with ditches 80 cm wide. Place seed ginger flat in the horizontal planting furrows, with ginger buds tilted slightly downward, so as to facilitate new roots emerging from the lower end of the seed ginger. The planting depth is 15 cm, and about 9000 plants are planted per 667 sq m. After planting, apply a small amount of calcium magnesium phosphate fertilizer, water thoroughly, then level the bed surface and cover with plastic film to help retain water and heat.

1.5 Field (greenhouse) management

(1) Temperature management Before ginger emerges, do a good job of heat preservation; small arched tunnels may be built, and after emergence, promptly break the film to guide the seedlings out so as to avoid burning the young stems and leaves. For small arched tunnels, pay attention to uncovering by day and covering at night. Greenhouse ventilation management depends on weather conditions, and it is appropriate to maintain the temperature at 25-30°C. When the temperature exceeds 30°C, cool it down to prevent excessive vegetative growth.

(2) Water management After emergence, the soil should be moderately dry to help raise ground temperature and promote emergence and root growth. During the entire growth period from full emergence to harvest, keep the soil moist, but prevent excessive wetness and water accumulation, so as to avoid excessive vegetative growth and disease occurrence.

(3) Ventilation and shading Ginger prefers shade and cannot tolerate strong direct sunlight; scattered light is more favorable for growth. In greenhouse cultivation, shade nets can be covered outside the greenhouse film before noon each day after late June.

(4) Intertillage, earthing up, and fertilizer-water management Intertillage and earthing up are carried out twice in combination with topdressing, the first in early April and the second around April 25; each time when earthing up, apply 40-50 kg of three-element compound fertilizer per 667 sq m.

(5) Pest and disease control For ginger blast, use soil disinfection, applying 100-150 kg of lime per 667 sq m; during the growth period, it may also be controlled by spraying with 20% Yekuning 1300-fold solution, once every 7-10 days, for 2-3 consecutive sprays; or drench the roots with 5% copper sulfate or 72% agricultural streptomycin 3000-4000-fold solution.

The main insect pest of ginger is the ginger borer; pesticides such as fipronil, Nongdile, and Chujin may be selected, generally starting control in mid-to-late May, once every 10 days, for a total of 2 times.

1.6 Harvest

Harvest of young ginger generally begins on March 20, with the peak harvest in June; the bulk ginger harvest is completed by the end of June, and harvesting can continue until mid-July.

2 Welsh onion cultivation techniques (following crop)

2.1 Variety selection

Select the Japanese variety Jinchang No. 3, which has good texture and long scallion white, as the main cultivar.

2.2 Sowing and seedling raising

For each 667 sq m of field, additionally prepare 66.7 sq m of seedling land, sow 0.15 kg of seed, using the broadcast sowing method, and sow as thinly as possible. The sowing period is set in early May. First water the seedbed thoroughly with bottom water, cover with soil after sowing and pat level, then cover with rice straw. After emergence, select the superior and remove diseased seedlings and field weeds, and apply one watering with dilute human manure.

2.3 Land preparation and planting

After the previous crop of ginger is harvested, clean up all debris in the field, plow and arrange it, do not apply basal fertilizer, arrange planting rows well, spray a commonly used fungicide once before planting, and plant at the end of July, with row spacing of 45-50 cm and plant spacing of 5 cm. When planting, the unfolded leaves between plants should be parallel, not crossing, so as not to affect later plant growth.

2.4 Field management

(1) Earthing up and fertilization Earthing up and fertilization are important farming operations for Welsh onion growth and are also the key technique for forming the scallion white, that is, the product organ. The principle of earthing up is: low in front and high in back, do not bury the heart leaves and do not damage the roots. Carry out earthing up on sunny days. Fertilization should emphasize nitrogen, include more potassium, and also take phosphorus into account. However, because the previous crop is ginger, a certain amount of fertilizer in the soil has not yet been utilized, so for the following crop of Welsh onion, only the following operations are needed: because of high temperatures in the early stage, Welsh onion grows slowly; in mid-September carry out the first weeding, intertillage and earthing up, and at the same time apply 10 kg of compound fertilizer per 667 sq m; the second time in early October, earth up and fertilize again, using 10-15 kg of compound fertilizer per 667 sq m; the third time in mid-November, combined with high earthing up, use 7-8 kg of urea per 667 sq m.

(2) Pest and disease control As the following crop after ginger, Welsh onion has relatively mild pests and diseases. Common diseases are rust and purple blotch, which can be controlled with 40% Fuxing emulsifiable concentrate 4000-6000-fold solution, 10% Shigao 1500-fold solution, 15% triadimefon 1500-fold solution, 80% Daconi M-45 wettable powder 600-fold solution, 72% Kelu 600-fold solution, and other pesticides. The common insect pest is onion thrips, which can be controlled with 5% fipronil suspension concentrate 2000-2500-fold solution.

2.5 Timely harvest

When the scallion white grows to about 30 cm and the stem diameter is 1.8-2.2 cm, it is the best harvest period, generally around New Year's Day, and harvesting is completed before the Spring Festival, after which the next year's ginger cultivation begins. If for export, harvest should be carried out according to the standards of the importing country, allowing the scallion white to grow to more than 35 cm, and grading and packaging should be carried out at the same time.

3 Output value composition

3.1 Greenhouse ginger

Production cost per 667 sq m: moso bamboo 1000 kg, totaling 600 yuan; greenhouse film 32 kg, totaling 400 yuan; skirt film 40 yuan; seed ginger 1000 kg, totaling 2400 yuan; fertilizers and others 1000 yuan; hired labor 10 days, totaling 500 yuan. Total 4940 yuan.

Output value per 667 sq m: at the start of harvest on May 20, the opening price averaged 14.00 yuan/kg; at the end of harvest in mid-July, the price averaged 6.00 yuan/kg; the average output value per 667 sq m over the years is about 14000 yuan, with the highest reaching 18000-20000 yuan.

3.2 Welsh onion

Production cost per 667 sq m: seeds 300 yuan; fertilizers and others 250 yuan; hired labor 5 days, totaling 250 yuan. Total 800 yuan.

Output value per 667 sq m: average yield per 667 sq m is 6000 kg, with the highest reaching 7500 kg; the average unit price over the years is 0.50 yuan/kg, with the highest once reaching 0.90 yuan/kg. Average output value per 667 sq m is 3000 yuan.

3.3 Output value of ginger-scallion rotation

The annual output value per 667 sq m is 17000 yuan; after deducting the cost of 5740 yuan per 667 sq m, the profit per 667 sq m can be 11260 yuan.