How are two crops of eggplant grown in one year? Which varieties are good to plant from 2018 to 2020? Master these key points and you too can grow two crops of eggplant in one year!

Eggplant is a fairly common vegetable on the dining table. Because of its high nutritional value and low price, it is widely eaten. At present, it is grown in most regions, and in most of those growing regions, it is one crop per year. In fact, eggplant can also be grown as two crops per year. So how are two crops of eggplant grown in one year? Which varieties are good to plant from 2018 to 2020?

1. Which varieties of two-crops-per-year eggplant are good to plant from 2018 to 2020?

Choose high-quality, high-yield varieties with a well-developed root system, strong growth vigor, strong branching, strong disease resistance, high-temperature tolerance, good marketability, and suitability for market demand. At present, the main varieties selected for overwintering eggplant ratoon cultivation in greenhouses in Jiashan County include Hangqie 2010, Hangfeng No. 1, and others.

2. How are two crops of eggplant grown in one year?

1. Sow at the right time and grow strong seedlings

(1) Seed treatment

The best sowing period for overwintering eggplant cultivation in greenhouses is early to mid-August. Before sowing, treat the seeds: soak the seeds in 55°C warm water for 15 minutes, then after disinfection soak them in clean water for 3-5 h, remove them, and wrap them in clean gauze or a wet towel. Germinate them at 28-30°C. After 24 h, check the seeds. When seeds with white sprouts appear, pick them out promptly, keep them moist, and place them in a container at 15°C. Once more than 80% of the seeds have sprouted white, they can be sown.

At sowing, water thoroughly to provide enough bottom water. The sowing rate is 1.5 g per sq m. After sowing, cover with 0.5-1.0 cm of nutrient soil, and cover the seedling bed surface with plastic film. Keep the seedling bed temperature at 28-30°C. After emergence, reduce humidity to prevent disease.

(2) Pricking out

When the seedlings grow 2-4 true leaves, divide the seedlings into nutrient pots. Pricking out is best done on a sunny day. After pricking out, water thoroughly to provide enough bottom water, cover with a small arch film, and add a shade net. On the 2nd day, ventilate appropriately. On the 3rd day, the film can be removed and the shading time reduced. Generally after 5 days, the shade net can be removed for normal management.

Control the daytime temperature at 20-28°C and the nighttime temperature at 15-20°C. Appropriately increase light duration, avoid excessively high humidity, and promote early root development.

After pricking out, additional seedling fertilizer can be applied according to seedling condition. When fertilizer is lacking, apply fertilizer together with watering: add 100 g of ternary compound fertilizer (N:P:K=15:15:15, the same below) per 50 kg of water.

2. Apply sufficient base fertilizer and transplant at the right time

Transplanting is best done in mid-to-late September, when the seedling age is about 45 days.

Before transplanting, apply 2000-2500 kg of decomposed organic fertilizer and 50 kg of ternary compound fertilizer per mu, or apply an equivalent amount of bio-organic compound fertilizer. Then plow deeply and make beds. The bed width (including ditches) is about 1.5 m, the ditch depth between beds is 20 cm, and the outer ditch depth is 40 cm.

Close the greenhouse 7 days before transplanting to raise the greenhouse temperature, lay drip irrigation under the film, and then cover with plastic film. When the seedlings are 20-25 cm tall, the stem diameter is more than 0.6 cm, and there are 7-8 true leaves, they can be transplanted. Choose a sunny morning for transplanting. Water the seedling bed thoroughly 1 day before transplanting. Plant 2 rows per bed, with a plant spacing of 35-40 cm, and transplant 2200-2500 plants per 667 m2.

3. Field management

(1) Temperature: After eggplant transplanting, keep the greenhouse closed for 3 days to promote seedling recovery. If the greenhouse temperature exceeds 40°C, ventilate appropriately to cool it down. In winter, use multi-layer covering for overwintering insulation. When the minimum temperature is 5-6°C, build a second film layer. When the minimum temperature is 0°C, build a third film layer. Keep the distance between films at more than 15 cm.

(2) Light: Management should focus mainly on increasing and preserving heat, while also taking into account light, moisture, air conditions, and other factors. Keep the maximum temperature inside the greenhouse at around 28°C, and maintain the minimum nighttime temperature above 10°C. Use multifunctional film with good light transmission, keep the film surface clean, and uncover insulation coverings during the day depending on weather conditions to increase light intensity and duration as much as possible.

(3) Topdressing: After transplanting, topdress promptly according to growth conditions. Apply 30-50 kg of ternary compound fertilizer per mu. After fertilizing, strengthen ventilation to prevent ammonia damage.

(4) Pruning: After the first eggplant flowers, remove all side branches below the first eggplant, and remove some leaves depending on growth conditions. When the plant shows a tendency to grow excessively, remove some functional leaves to inhibit excessive growth.

Especially when the fruit-setting rate is low, pruning and leaf removal should be done even more promptly, and the extent of pruning should be greater, to achieve the purpose of ventilation and light penetration. During low temperatures in winter, fruit-setting hormone can be used to dot flowers, improving the fruit-setting rate and ensuring eggplant yield.

4. Harvest at the right time

Eggplant takes about 20 days from flowering to harvest. Early fruits such as the first eggplant and opposite eggplant should be harvested promptly to facilitate the growth of later fruits. Once entering the peak fruiting period, harvest once every 3-4 days.

The harvest period should take into account market prices and plant growth vigor. When growth vigor is excessive, appropriately delay picking. When growth vigor is weak, harvest appropriately earlier. In Jiashan County, overwintering eggplant ratoon cultivation in greenhouses generally harvests from late November until the end of June the following year, after which no more fruits are retained and no pruning is done, and the plants are rejuvenated.

5. Pruning regeneration technology

In the high-temperature summer season, open-field eggplant is being marketed in large quantities, and overwintering eggplant in greenhouses begins to show poor growth, reduced yield, poor quality, and rapidly falling market prices. Therefore, overwintering eggplant in greenhouses in Jiashan County is generally harvested until the end of June, after which no more fruits are retained, and a one-time pruning is carried out in late July to early August.

Use scissors to cut off the entire top of the plant, retain 3-4 strong-growing side buds for scientific cultivation, remove the remaining young buds and old leaves, and apply 25-30 kg of ternary compound fertilizer with water.

After pruning, because the external temperature is high and the large root system absorbs nutrients, harvest can generally be carried out about 30 days after pruning. Generally, after the first regenerated eggplant crop is harvested, the plants are pulled up to clear the field and arrange the next crop.

6. Pest and disease control

The main diseases harming eggplant include gray mold, early blight, bacterial wilt, and others; the main insect pests harming eggplant include thrips, tea yellow mites, and others.

Follow the plant protection policy of “prevention first, integrated control”, and adhere to the harmless management policy of “agricultural control, physical control, and biological control as the main methods, with chemical control as supplementary.”