Detailed Explanation of Key Technical Points for Garlic Field Planting and Management
Garlic (Garlic), also called suan tou, da suan tou, hu suan, hu, du suan, du tou suan, is the collective name for plants of the garlic group. A half-year herbaceous plant of the lily family, Allium genus, with its bulb used medicinally. Harvest in spring and summer, tie into bundles, hang in a ventilated place, and dry in the shade for later use. As the farming proverb says “plant garlic before the ninth (month), after the ninth it grows single heads”, when the leaves wither in June dig it up, remove the mud and sand, and dry in the shade or bake until the outer skin is dry.
Nutritional value of garlic
Garlic is rich in nutrition: every 100 grams contains 69.8 grams of water, 4.4 grams of protein, 0.2 grams of fat, 23.6 grams of carbohydrates, 5 mg of calcium, 44 mg of phosphorus, 0.4 mg of iron, and 3 mg of vitamin C. In addition, it also contains thiamine, riboflavin, niacin, allicin, citral, and trace elements such as selenium and germanium. It contains about 0.2% volatile oil, and the main component of the oil is allicin, which has a bactericidal effect and is produced when the alliin contained in garlic is hydrolyzed under the action of alliinase. It also contains various sulfur ether compounds composed of allyl, propyl and methyl groups. Garlic contains “alliamine”, and this substance is many times more beneficial to the brain than vitamin B. Letting children eat more scallions and garlic in daily life can make the growth and development of brain cells more active.
Next, let us look at how garlic should be planted and what needs attention.
Land selection
Garlic has a strong ability to adapt to soil and can grow in all soils except saline-alkali land. However, because garlic has a shallow root system and weak absorption capacity, sandy loam rich in organic matter and fertile is suitable. According to the characteristics of the garlic root system, deep plowing and fine harrowing are required, the bed surface should be level, and sufficient decomposed organic fertilizer should be applied before sowing.
Apply sufficient base fertilizer
For fields with average soil fertility, 4000 kg of decomposed pig manure or other high-quality organic fertilizer per mu, or 100 kg of compound fertilizer per mu, can be used. For cultivation for garlic heads, add 15 kg of potassium sulfate per mu.
Sowing
1 Variety: The special variety for garlic scapes is “Er Shui Zao” from Chengdu, Sichuan, the special variety for garlic heads is Xuzhou white garlic, and the dual-purpose varieties for both garlic heads and garlic scapes are “Jiading No. 1” and “Jiading No. 2” white garlic and Shandong Cangshan garlic.
2 Sowing time: The suitable sowing time for harvesting garlic heads and garlic scapes is late August to early September, and for harvesting garlic sprouts it can be sown from mid-August to September. It is not too late to sow garlic scapes now; sow as soon as possible, and cover with plastic film after 70% have emerged.
3 Sowing method: The garlic cloves broken off from the garlic head carry a small piece of lignified stem plate, which must be removed before sowing; otherwise the bottom cover absorbs water and rots, hindering bud germination. After the seed cloves are broken off, they must not be piled together, but should be spread out evenly to avoid the seed pile heating up and affecting germination and seedling growth. Before sowing, the seed cloves are best soaked in water for 1-2 days, so that the seed cloves absorb enough water and root faster.
When sowing, generally place the selected seed cloves along the sowing furrow with the back of the clove (that is, the protruding side facing south) in the previously opened sowing furrow, then cover with soil; after watering, the cloves can be slightly exposed. In fields sown this way, the seedlings emerge neatly and the tips of the seedlings point in one direction within the row, making field management operations convenient.
4 Sowing rate: The sowing rate and density differ according to cultivation purpose. For harvesting garlic heads or garlic scapes, the row and plant spacing is (16-26)×(10-13) cm, with 100-150 kg per mu. For producing garlic sprouts, sowing is denser, with row and plant spacing of 13×5 cm, and the sowing rate reaches 1000 kg per mu.
Field management
1 Film covering. After sowing and emergence, cover with plastic film when the seedlings are level with the ground, use wire to cut openings so the seedlings emerge easily, then cover with soil and earth up around the roots to aid growth. The film cannot be covered before the seedlings emerge, otherwise the high temperature is unfavorable for emergence. Covering with plastic film can increase temperature and preserve moisture, retain fertilizer and increase efficiency, improve the soil, prevent insects and suppress weeds, and promote the development of garlic plants for early maturity and high yield.
2 Fertilizer and water management for producing garlic sprouts: To produce garlic sprouts, fertilizer should be applied frequently. The first time is after the garlic sprouts have all emerged, apply human excrement or pig manure urine, 500-750 kg per mu. During the leaf growth period, apply additional fertilizer 2-3 times in stages depending on the growth situation.
Fertilizer and water management for producing garlic scapes: Apply a quick-acting fertilizer (human manure urine or ammonium bicarbonate) once at the 2-leaf stage of garlic to promote seedling growth. Before overwintering (late November), irrigate to prevent freezing and protect the seedlings, and promptly cultivate and apply winter fertilizer, applying 1500 kg of human manure urine or pig manure urine per mu or 3000 kg of other high-quality organic fertilizer. After overwintering, during the garlic green-return period (before Qingming), continuously water twice early with green-return water; the first watering carries 40 kg of ammonium bicarbonate per mu, and after watering shallow cultivation is done to preserve soil moisture.
3 Hormone treatment. When the garlic scape just shows its tip, treat with 920 (gibberellin produced by Shanghai Factory 18), which can speed up bolting. Method of using 920: dissolve each gram with alcohol, then add 50 jin of water and spray on the surface of the garlic.
4 Promote garlic head growth. After harvesting the scapes, apply 40 kg of ammonium sulfate per mu to make the garlic heads expand rapidly. If the leaves are found to turn black, this is a sign of water shortage, and timely irrigation is needed to make the garlic heads expand. Stop watering one week before harvesting the garlic heads to promote drying of the outer skin and move the nutrients in the stems and leaves toward the garlic heads.
5 Pest and disease control. Garlic has fewer diseases, and is mainly afraid of damage from maggots and thrips. Maggot damage mostly occurs before the new year and during the rotten mother period after green return, while thrips begin to cause damage in mid-April. Control method: combine with watering and add pesticide for irrigation twice; 800-1000 times dilution of 90% trichlorfon can be used per mu to irrigate the roots.
There are techniques for topdressing garlic
For autumn-sown garlic, topdressing should be applied once each at the seedling stage and before overwintering, and the fertilizer used can be human manure urine or chemical fertilizer, etc. Generally, 1000~2500 kg of decomposed human manure urine per mu, or 15~20 kg of ammonium sulfate, or 7~9 kg of urea, applied with water. If the garlic seedlings grow vigorously, topdressing can be omitted to prevent excessive seedling growth before winter. When overwintering, cover with wheat straw or rice straw, and spread soil miscellaneous fertilizer, pond mud, etc., 5000~7000 kg per mu, which can make the plants bolt early the next year, with large garlic cloves and heavy garlic heads. After the temperature rises in spring, in order to meet the nutrient demand of the spring growth stage, apply a spring fertilizer in time, and human manure urine or chemical fertilizer can be used. When bolting, apply another 20~25 kg of ammonium sulfate per mu, or 9~12 kg of urea. One month after applying the bolting fertilizer, the garlic bulbils enter a period of vigorous development and need a relatively large amount of nutrients. At this time, apply a quick-acting fertilizer once; 3000~4500 kg of pig manure urine per mu, or 18~20 kg of ammonium sulfate, or 8~10 kg of urea can be applied, which can prompt garlic to bolt early and improve the yield and quality of garlic scapes and garlic heads. When fertilizing garlic, attention should be paid to fertilization at two key periods: first, the seedling-promoting fertilizer, to promote garlic leaf growth, and second, the head-promoting fertilizer, to promote the expansion of the garlic bulb.