Detailed Explanation of Key Points for High-Yield Cultivation Techniques of Bolting Garlic

Bolting garlic is grown for the purpose of producing garlic scapes and garlic bulbs as vegetables, and it holds relatively high value in vegetable cultivation. Its high-yield cultivation techniques are described as follows:

1. Land preparation and fertilization: Bolting garlic is suitable for planting in loose, fertile sandy loam or loose-textured plots. During land preparation, deep plowing and fine harrowing should be carried out to achieve depth, fineness, thoroughness, firmness and levelness. Garlic has a high fertilizer demand, and heavy fertilization is the foundation for high yield. Generally, per 667 sq m (1 mu), apply 4000-5000 kg of fully decomposed organic fertilizer, 50 kg of diammonium phosphate, 30 kg of potassium sulfate, 3 kg of iron fertilizer, 2 kg of zinc fertilizer and 2 kg of boron fertilizer. Apply all of these together with the plowing and turning of the soil.

2. Variety selection: Choose Cangshan garlic, which is dual-purpose for scapes and bulbs, vigorous in growth, highly adaptable, cold-resistant, high-yielding and of good commercial quality, as the cultivation variety. Select cloves that are large, white in color, sterile and undamaged as garlic seed. Grade the seed cloves into large, medium and small, and sow according to grade.

3. Fine sowing: In Shandong Province, sowing in early October is appropriate. For planting density, the row spacing is 18-20 cm and the plant spacing is 10 cm, with 34000-38000 plants per 667 sq m. Generally, sow in furrows 6 cm deep. After the seed cloves are sown into the soil, rake the furrows level, cover with 2-3 cm of soil, and firm and flatten. Spray 100-150 g of 48% trifluralin emulsifiable concentrate per 667 sq m, immediately cover with plastic film, seal the edges of the film tightly with soil, and then give one thorough watering.

4. Strengthen management: Garlic emerges 7-9 days after sowing. Most garlic sprouts can break through the film and emerge, while a few garlic seedlings must be helped through the film manually in time by guiding the seedlings out of the film. From "Minor Snow" to "Major Snow", before the soil freezes, water once with overwintering water. When the garlic seedlings turn green again the following spring, water once with green-up water. Entering April, the garlic seedlings begin vigorous growth, so give one thorough watering and topdress, applying 25 kg of urea per 667 sq m. From early May to before scape harvest is the period of vigorous garlic scape growth. At this time, attention should be paid to watering and the soil surface should be kept moist. In early May, water once, and together with watering, apply 25 kg of nitrogen-phosphorus-potassium compound fertilizer per 667 sq m by flushing. After harvesting the scapes, water in time and keep the soil surface alternating between dry and wet, stopping watering 7 days before harvesting the garlic bulbs.

5. Timely harvest: Entering mid-to-late May, when the garlic scape flower bud becomes larger, turns white in color, and the top of the scape bends into a hook shape, this is the best harvest period, and the scapes should be harvested in time. About 20 days after scape harvest, when the upper leaves of the garlic turn grayish green, the lower leaves wither and fall off, the garlic stem becomes soft, and the garlic bulbs have fully expanded, harvest in time to avoid black skin and loose cloves in the garlic bulbs, which would affect product quality.

6. Disease control: The main garlic disease is leaf blight. In severely affected areas, spray pesticides in advance for protection. (1) Grasp the best control timing. The disease is prone to occur in April-May, so prevention should be emphasized to control the occurrence of the disease. After each rainfall, drain water in time and spray pesticides in time. (2) Choose suitable pesticides and use them alternately. The suitable pesticides mainly include 75% chlorothalonil wettable powder at 1000 times solution, 40% carbendazim suspension concentrate at 800 times solution, and 64% oxadixyl-mancozeb at 500 times solution.