(1) Cultivation season. Holding the son of kale and kale can be cultivated in the open field in spring and fall, in order to achieve higher efficiency, it is best to use the improved sun beds or greenhouses without heating in the spring early, after the fall delayed cultivation.
①Spring improved sun beds or unheated greenhouse cultivation. It is advisable to use early-maturing varieties such as early child holding, the ball period is more resistant to high temperatures. Seedlings in January, mid-protected, mid-February, late planting, mid-May, late to early June harvest.
②Spring open field cultivation. Early child holding varieties, in January in the middle and late seedlings, in March in the middle of the buckle shed or improved film early planting, in June in the middle of the harvest.
3 fall open field cultivation. The use of precocious varieties of Gis and Lu, sown in mid- and late-June, mid- and late-July planting, mid- and late-October to early-November harvest.
④Autumn improved sunbeds or unheated greenhouse cultivation. The use of medium-maturing varieties of Zengtianzi hold, still sown in mid- and late-June, planted in mid- and late-July, harvested in mid- and late-November.
(2) cultivation technology points.
①Sowing seedlings.
a. Sowing method. Early spring is appropriate to use greenhouse seeding, easy to meet the requirements of seedling growth of about 22 ℃ suitable temperature conditions. Summer seedling can be used plastic large and medium-sized shed seedling, and covered with old agricultural film shade, rain, surrounded by large ventilation, conducive to cooling. Planting 667 meters 2 hug son kale need to prepare 4 meters 2 nursery beds. Before sowing, pour enough bottom water, sprinkle fine subsoil before sowing. Planting 667 m 2 of seed amount of 20 ~ 25 grams, after sowing covered with fine soil to cover the seeds, moisture retention. When the seedlings grow 2 true leaves, select strong seedlings, according to the plant spacing 12 cm × 15 cm seedling.
b. Seedling management. After sowing in early spring, the seedbed is kept at about 22 ℃, 18 ℃ after the emergence of seedlings, and then reduced by 2 to 3 ℃ before seeding. Seedlings before, after slowing down, before planting can still refer to the above temperature to manage. Shade and water properly in summer to lower the temperature. Seedling period of the bottom watering enough watering basically do not water. Water thoroughly after seeding, and then replenish water as appropriate. In summer, depending on the weather conditions, more watering is appropriate, which is conducive to growth and cooling.
②Planting. Holding son of kale seedling age varies with the different nursery seasons, generally 40 days in early spring, summer and fall less than 30 days. When the seedling has 5 true leaves for the planting of the appropriate period. Before planting, apply enough fertilizer, prepare the ground and make beds. Every 667 meters 2 to apply high-quality rotting farmyard fertilizer more than 2500 kg, 15 kg of diammonium phosphate, 20 kg of calcium superphosphate. Middle-ripe species should be planted in a single row, made of small raised beds 1.2 meters wide with ditch, plant spacing 40 to 50 cm, planting 1200 plants per 667 m 2; dwarf early-ripe species made of small raised beds 1.4 meters wide with ditch, planted in 2 rows per bed, plant spacing 50 cm, planting 1800 to 2000 plants per 667 m 2. When planting seedlings, we should try to keep the soil pile not scattered, to protect the root system, and promote the slowing down of seedlings.
3 Field management.
a. Water and fertilizer management. After planting, planting water should be watered sufficiently, 5 to 7 days (3 to 4 days in summer) after watering seedling slowing water, squatting seedlings during the period to pay attention to plowing and weeding. Holding the son of kale long reproductive period, from planting to the end of the harvest, the growth period of up to 90 to 120 days, the need for fertilizer 3 to 4 times. The first time in the planting of survival, every 667 m 2 of urea about 10 kg, in order to facilitate the recovery of plant growth. If you have already applied enough bottom fertilizer, this time can be omitted. The second fertilizer in 30 days after planting, to promote plant nutrient growth, so that its outer leaves up to about 40 pieces and then enter the ball stage. After two fertilizer need to cultivate the soil, to prevent plant inversion and fertilizer loss. The third fertilizer in the leaf ball expansion, to promote the development and expansion of the leaf ball. The fourth fertilizer in the leaf ball harvesting period, because each plant has 25 to 40 small leaf ball, when the lower part of the leaf ball harvested one after another, the upper part of the leaf ball continues to form, but also need nutrients and water, at this time the fertilizer is conducive to improve the yield. After 3 times of fertilizer, each 667 m 2 each time to apply urea 15 kg, balling period can be foliar spray 0.3% potassium dihydrogen phosphate solution, every 5 days to spray 1 time, even spray 3 times.
b. Plant adjustment. Holding son kale plants tall, the number of leaves, the leaf ball is constantly forming, easy to cause the plant head heavy, causing collapse, affecting yield and quality. General plant growth to 40 cm, according to different varieties, should choose the appropriate length of the frame pole insertion frame, the upper part of the rope tied, in order to prevent the collapse; for the base of the plant ball poor axillary buds and diseased leaves should be removed in a timely manner to reduce the water, nutrient consumption, is conducive to the ventilation and light.
Hugger kale per 667 meters 2 production varies according to varieties, cultivation methods and cultivation techniques, single ball weight is generally 100 ~ 150 grams. High-yield species and cultivation management, every 667 meters 2 production can reach 500 to 600 kg; low-yield or cultivation management is not lawful, every 667 meters 2 production can only have 150 kg.