When Is the Best Time to Plant Garlic? Timely Sowing Is the Key to Growing Good Garlic

Garlic is an essential seasoning in daily life; you cannot do without it when cooking or stir-frying. In recent years, people have discovered many pharmacological effects of garlic, finding that it can prevent and treat a variety of diseases. American scientists have already listed garlic as a basic health food. At present, garlic has become a worldwide vegetable, and in some countries that rely entirely on imports, the price of garlic is relatively high. Garlic is suited to growing in cool climatic conditions; it dislikes heat and fears cold. The Yellow River basin in China is a suitable growing area for garlic, and at present some places have become the main garlic production areas and export bases in China. The garlic sowing season has come around again, so the garlic cultivation techniques are briefly introduced below for farmers' reference.

I. Select excellent varieties. At present, the varieties grown more widely in our area mainly include Songcheng garlic, Songcheng white garlic and Cangshan garlic. According to incomplete statistics, the planting area of Songcheng garlic is over 75%; Songcheng white garlic is the preferred variety for export; Cangshan garlic is a mid-to-late maturing variety used for both scapes and bulbs.

II. Sow at the right time. Garlic is a crop that prefers cool conditions and has the characteristic of natural dormancy. If sown too early, it will emerge slowly because it is still in the dormant period; after emergence, the high early-season temperatures and excessive pre-winter growth will greatly weaken the cold resistance of the garlic seedlings, and in the later growth stage the lower leaves of the plant are also prone to turning yellow and premature senescence. If sown too late, the garlic seedlings will be small before overwintering, accumulate little nutrients and have weak cold resistance. In particular, sowing too late shortens the growth period of stems and leaves, resulting in fewer leaves, but the bulb maturity period is the same as or slightly later than that of early sowing, so the bulbs are smaller, yields are low and quality is poor.

In our area, sowing around the Autumn Equinox is appropriate. About 10 days after sowing, full emergence can be achieved, and before overwintering the plants can have 5-6 leaves, with relatively strong cold resistance.

III. Sowing density. The size of the garlic seed is closely related to how many nutrients it contains. Large cloves mean sufficient nutrients, and after emergence the plants have well-developed root systems, more leaves and thick, long false stems; at harvest the scapes are thick, the bulbs are large and the cloves are large, giving better market quality. Therefore, when sowing, choose larger cloves as seed as far as possible. Taking Songcheng white garlic as an example, cloves weighing 4-5 grams can be selected as seed, with a seeding rate of 130-150 kg and about 33,000 plants per mu. If cloves weighing 3.5-4.0 grams are used as seed, the density per mu can be increased to about 35,000 plants.

IV. Land preparation and sowing. To achieve high quality and high yield of garlic, sufficient base fertilizer must be applied at planting. The previous crops for garlic are generally corn, peanuts, watermelon, etc., and after these crops are harvested there is very little time before garlic planting. Therefore, after harvesting the previous crop, fertilizer should be applied promptly; per mu, 500 kg of decomposed chicken manure and 50 kg of diammonium phosphate can be applied. After application, plow and rake level, mark lines at 80 cm, and using the lines as a guide, shovel soil to both sides with a spade to make high beds 10 cm high and 50 cm wide at the top. Every 3 beds, a high bed ridge 15 cm high can be made to hold water when irrigating. On both sides of the high bed ridges, two more rows of garlic can be planted. On the leveled 50 cm wide high bed, open 4 furrows 6-7 cm deep, place garlic cloves at a spacing of 10 cm (33,000 plants per mu), then cover with soil, fill the furrows level, and immediately water to settle the cloves, so as to prevent the cloves from being pushed out of the ground when they take root and emerge.

V. Mulching with plastic film. In garlic cultivation, mulching with plastic film can increase bulb size and raise yields. Generally, after garlic is sown and emerges, air temperature and soil temperature have already begun to drop; at this time, if 80 cm wide plastic film is used for mulching, a noticeable effect of increasing temperature and preventing cold damage can be achieved. When mulching, first pull the film straight and tight and bury it in the soil, then make holes in the film directly over the seedlings, and use a wire hook to pull the seedlings out one by one.

VI. Field management

1. Spraying herbicide: 2-3 days after sowing, spray 24% Goal herbicide to chemically control weeds in the field. The dosage per mu is 50-60 ml, mixed with 50 kg of water, and sprayed evenly over the whole field. When spraying, walk backward to avoid damaging the herbicide film in the beds and reducing the weeding effect. Goal herbicide can be used after garlic sowing and before emergence, or after emergence, as long as the 1-2 leaf stage of garlic is avoided. In addition, using 50 g of 60% butachlor or 120 g of atrazine mixed with 50 kg of water and sprayed before emergence also has the same weeding effect.

2. Water and fertilizer management: before overwintering, the growth of the seedlings mainly depends on the nutrients in their cloves, so no topdressing is needed, and watering can be done according to soil conditions. In late December, a "freezing water" irrigation should be given so that the garlic seedlings can overwinter safely. In early March, flower buds (scape primordia) and bulbils (clove primordia) appear one after another, but growth is very slow; from late February to mid-April, plant growth is mainly focused on expanding leaf area. Only when the average temperature of the ten-day period reaches above 10°C will scape growth accelerate. Therefore, in late February, along with watering, 10 kg of urea or 15 kg of ternary compound fertilizer can be flushed onto the field per mu.

VII. Control of pests and diseases

The main insect pests of garlic include aphids, onion thrips, garlic maggots, etc., with onion thrips being the most widespread, especially in dry years with little rain, when damage by onion thrips is even more severe. Its adults and nymphs use piercing-sucking mouthparts to suck leaf sap, and many grayish-white spots appear on damaged leaves. When pest infestation is found, promptly spray a mixture of 40% dimethoate emulsifiable concentrate and 80% dichlorvos emulsifiable concentrate at 1500 times dilution, or 10% imidacloprid wettable powder at 2500 times dilution.

The damage caused by garlic maggots in garlic production is not widespread; it occurs only in isolated places due to the use of undecomposed organic fertilizer or because adult flies are attracted to lay eggs when the garlic seed "rots at the mother bulb." After the eggs hatch, the larvae enter the soil, gnaw the garlic roots and false stems, causing rot. In mild cases, leaves turn yellow and plants are short, affecting yield; in severe cases, plants die. To control garlic maggots, put 1000 times diluted dimethoate emulsifiable oil, chlorpyrifos or phoxim into a sprayer, remove the spray disc, and apply the solution into the soil around the roots. Note that highly toxic pesticides must never be used.

The main diseases of garlic include purple blotch, gray mold, etc. After the diseases occur, 75% chlorothalonil, 64% oxadixyl-mancozeb, 50% iprodione, 70% thiophanate-methyl and other agents can be used alternately at 600-800 times dilution for spray control.

VIII. Harvest at the right time

1. Harvesting scapes: Songcheng white garlic has weak scape growth, and the scape can be pulled when it extends 6-7 cm out of the leaf sheath. For some varieties with strong growth, the scapes are thicker and break easily when pulled, so the stick-piercing method can be used. That is, use a bamboo skewer with a sharpened tip; when pulling the scape, hold the scape with one hand and insert the bamboo skewer into the stem with the other hand (at 5-7 cm above the ground on the false stem), cut the scape, and then pull the scape out.

2. Harvesting bulbs: Songcheng white garlic can be harvested about 25 days after the scapes are harvested (when the false stems lodge). For other varieties whose false stems do not lodge, harvest can be done when the basal leaves begin to turn yellow and the outer skin of the bulbs becomes thin. If mature garlic is not harvested in time, especially in rainy conditions and when soil moisture is high, the outer garlic skin is very prone to turning black and rotting, and it easily leads to clove separation.