When Is the Best Time to Plant Garlic? Plus Key Cultivation Techniques

Garlic is a garlic-type plant whose roots, stems and leaves can all be eaten. Its bulbs, leaves and scapes can all be eaten as vegetables, and can also be used as a seasoning to add fragrance to dishes. Garlic is rich in nutritional value and also has a certain health-care value. Garlic is planted in many places in our country, so when is garlic generally better to plant? Plus cultivation techniques key points.

I. When is garlic generally better to plant?

The most suitable 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 frozen to death in the severe winter, and lay a good foundation for the plants to pass through vernalization smoothly. In the Yangtze River basin and areas to its south, sowing is generally done in mid to late September.

In September the weather in the Yangtze River basin is cool, suitable for garlic seedlings to emerge and grow. If sown too early, the seedlings grow too vigorously before overwintering and consume nutrients, which lowers their overwintering ability; they may also undergo vernalization again, causing secondary growth and forming multi-clove garlic the next year, reducing garlic quality. If sown too late, the seedlings are small, the tissues are tender, the root system is weak, less nutrients are accumulated, cold resistance is lower, and many die during the overwintering period. Therefore the sowing period of garlic must be strictly controlled.

II. Key points of garlic cultivation techniques

1. Garlic seed selection

It is very important to choose suitable garlic varieties according to the different parts to be harvested. According to clove size, garlic can be divided into large-clove garlic and small-clove garlic. For those mainly harvesting garlic sprouts (garlic seedlings), choose early-maturing varieties of small-clove garlic, such as white-skin garlic, which has a short growth period and comes to market early. For those mainly harvesting scapes and bulbs, choose large-clove garlic with larger cloves, mainly purple-skin garlic varieties. To ensure yield and quality, the seed garlic should be chosen from cloves of uniform size, free of mildew and rot, and with a good stem plate. Before sowing, peel off part of the garlic skin and remove the small cloves.

2. Garlic sowing methods

Before sowing, the garlic can be sun-dried for 1-2 days. To prevent mildew and rot after sowing, the seed garlic can be soaked in carbendazim for 4-6 hours. Green garlic (garlic seedlings) generally requires a plant spacing of 2-3 cm and a row spacing of 13-17 cm, with 250-350 kg of seed used per mu; for those mainly harvesting scapes and bulbs, a plant spacing of 7-8 cm and a row spacing of 14-17 cm is generally required, with 150-200 kg of seed used per mu. Reasonable close planting not only ensures quality but also ensures yield. The sowing depth is generally 3-4 cm; too deep or too shallow both affect emergence.

3. Water and fertilizer management for garlic

According to the growth and development of garlic and its fertilizer requirements, decomposed organic fertilizer (farmyard manure) is generally the main fertilizer, supplemented by chemical fertilizer. Base fertilizer is applied before plowing for sowing; generally 1000-2000 kg of organic fertilizer per mu is needed, together with 50 kg of ternary compound fertilizer. Garlic topdressing is generally mainly nitrogen fertilizer, supplemented with phosphate fertilizer and potassium fertilizer, etc. Nitrogen fertilizer has a significant promoting effect on increasing garlic yield. Topdressing can generally be carried out in different periods, specifically divided into topdressing at the greening stage, the scape elongation stage and the bulb growth stage.

Topdressing at the greening stage: generally when the garlic seedlings resume green growth and the average daily temperature in spring reaches about 7°C, topdressing begins, generally 10-15 kg of nitrogen fertilizer per mu or 1000-1500 kg of organic fertilizer. When growing green garlic (garlic seedlings), it is generally harvested when the seedlings are about 20 cm, so in terms of topdressing there is no need to consider topdressing at the scape elongation stage and the bulb growth stage.

Topdressing at the scape elongation stage: for harvesting scapes, topdressing at this period is especially important. This period runs from clove differentiation and growth to before the scape elongates, generally carried out before Qingming. At the same time, during this period the garlic bulbs also begin to swell, so this topdressing accounts for about 40% of the total topdressing amount, and compound fertilizer and phosphate fertilizer should be applied to promote bulb swelling and growth. Topdressing at the bulb growth stage: this is the last fertilization before garlic harvest. This period is dominated by bulb swelling and growth, so nitrogen fertilizer should be mainly applied, together with compound fertilizer and phosphate fertilizer, and the topdressing amount accounts for 25%-30% of the total. The main garlic fertilization methods are applying with water, burying and banding.

4. Irrigation of garlic

The whole process generally requires 3-4 waterings. First, after sowing, water thoroughly; second, seedling-strengthening water, combined with topdressing at the garlic greening stage, to promote the absorption of fertilizer and water; third, scape-emergence water, watering begins as soon as the garlic scapes just show their tips, to promote scape elongation; fourth, swelling water, watering begins after the scapes are pulled, combined with topdressing at the bulb growth stage to promote rapid bulb swelling.

5. Pest and disease control and harvest of garlic

During the 5-6 leaf growth stage of garlic, spray chlorothalonil, prochloraz, etc. to control garlic purple blotch, rust, etc. During the growth period, use carbosulfan, etc. to control pests such as thrips. Different pesticides should be used alternately to prevent pests from developing resistance. For garlic harvest, the bulbs can generally be harvested 20-30 days after the scapes are all pulled.