Detailed Explanation of Key Techniques for High-Yield Cultivation of Garlic with Plastic Mulch

The yield-increasing effect of plastic mulch on garlic is very obvious. Compared with open-field cultivation, garlic under plastic mulch has significantly better roots, stems and leaves than open-field garlic; the yield of garlic scapes is 35% higher than open-field cultivation, and the yield of dry garlic bulbs is 30% higher than open-field cultivation. Its main cultivation techniques are:

1. Sowing at the right time. The optimal period for sowing garlic is to let the plants grow to 5-6 leaves before overwintering; at this time the plants have the strongest cold resistance, will not be killed by freezing in the severe winter, and lay a good foundation for the plants to successfully pass vernalization. The suitable sowing period for plastic-mulch garlic, from the Beijing area to the Handan area, is roughly between the two solar terms "Autumn Equinox" and "Cold Dew," that is, from the end of September to the beginning of October.

2. Carefully selected varieties. To ensure the quality of garlic seed, when selecting seed, choose standard garlic bulbs that are large and round, with a flat and non-deformed base, large and compact cloves, thick skin that tolerates storage and transport, and conform to the characteristics of the variety. Generally, Cangshan garlic is used; for Yongnian County, which mainly produces garlic scapes, Cangshan Puke garlic is used.

3. Apply sufficient base fertilizer. Garlic is a fertilizer-loving crop; it needs a lot of fertilizer and is also tolerant of fertilizer. The fertilization principle for planting garlic is to rely mainly on base fertilizer and supplement with topdressing. The ratio of base fertilizer to topdressing should be reasonable. For plastic-mulch garlic, generally 5000 kg of high-quality farmyard manure, 100 kg of ammonium bicarbonate, and 100 kg of superphosphate are used per mu as base fertilizer. Plow, harrow finely, and make beds; the bed width is 166 cm.

4. Seed treatment. Tests have shown that for 100 kg of garlic seed, first soak the seed for 6 hours in a 0.3% potassium dihydrogen phosphate aqueous solution, then treat it before sowing with 500 g of 50% carbendazim powder. This can not only promote earlier emergence and prevent disease, but also advance maturity and increase yield. Using 150 g of 50% procymidone plus 2 kg of water to evenly mix 200 kg of seed gives a very good effect in controlling sclerotinia rot.

5. Sowing. In the bed, open 8 furrows at a row spacing of 20 cm, with a furrow depth of 3-4 cm, and plant by hand in the furrows, placing the garlic cloves vertically into the soil. For garlic mainly grown for scapes, 45,000-50,000 plants per mu (plant spacing 6-7 cm); for garlic mainly grown for bulbs, 25,000-30,000 plants per mu (plant spacing 10-12 cm). Then rake level and cover with soil; after covering, the soil above the garlic sprouts should be about 0.5-1 cm thick. Rake the bed surface level.

6. Watering and mulching. After sowing plastic-mulch garlic, water and mulch according to temperature and soil moisture. If the daily average temperature is above 20°C and the weather is dry, do not rush to water and mulch after sowing; wait until the daily average temperature drops to about 17°C before watering and mulching. If the temperature is suitable, regardless of whether the soil moisture is good or bad, water promptly after sowing, spray herbicide, and mulch. If the temperature is on the high side and the soil moisture is good, 2-3 days after sowing, after the seed cloves have set roots, water and mulch.

7. Breaking the film to release seedlings. Once garlic is found to be sprouting and pushing up the film, promptly concentrate labor and seize the time to release the seedlings. After the seedlings are fully emerged, water once more. In early December, according to weather conditions, water the freezing water at the appropriate time.

8. Strengthen management. Garlic covered with plastic mulch can overwinter safely and can quickly enter the green-up stage after the temperature rises. Generally, in late February to early March of the following year, water the green-up water well, and apply 25 kg of urea per mu with the water. If garlic maggots are found, apply 1 kg of 50% phoxim per mu with the water; the control effect is very good. In early April, garlic enters the flower bud differentiation stage; to promote its growth, topdressing and watering are required. Apply 20 kg of ammonium bicarbonate or 25 kg of urea per mu with the water. After garlic scapes are harvested in early May, the garlic bulbs enter the enlargement stage; promptly water enough water for garlic bulb enlargement, and apply human feces and urine or chemical fertilizer. If there is premature senescence of garlic seedlings, foliar fertilization can be carried out by spraying with a 500-700 times dilution of potassium dihydrogen phosphate or 2% urea. From late May to early June, harvest, dry, and store promptly.