High-yield cultivation techniques of spinach

Spinach belongs to Chenopodiaceae and belongs to 2012 herbs. Also known as red root vegetables, Persian food. Originally from Persia to Iran, it was introduced into China in the Tang Dynasty. It has a long history of cultivation and is widely planted in the north and south of our country. It has wide adaptability, strong cold tolerance, storage resistance, long supply period, easy to grow and harvest quickly, and high yield. the product can be supplied in early spring and off-season in autumn and winter. it is one of the important vegetables in autumn, winter and spring in north China. Spinach is green, tender and delicious, rich in nutrients and rich in vitamins and mineral elements. it is a kind of vegetable with high nutritional value.

Biological characteristics of spinach

1. Botanical characteristics

① root. Spinach has deeper taproots and is more developed. Taproot slightly thicker and slightly inflated, upper red, stored nutrients, sweet and edible. The main root groups are distributed in the plough layer of 25~30cm. The lateral root is not developed and is not suitable for transplanting.

② stem. The vegetative growth period is short stem, and the flower stem is elongated and high 66~100cm during reproductive growth.

③ flowers. The flowers of spinach are unisexual and a few have bisexual flowers. Dioecious, a few monoecious. Male flowers spikes, inserted in top of stem or leaf axils, apetalous, calyx 4-lobed, stamens as numerous as calyx. Anthers longitudinally lobed, many pollen, yellowish green, wind-pollinated flowers. Female flowers clustered in leaf axils, apetalous, with 1 pistil, stigma 4-6, calyx 2-4-lobed, enclosing ovary, ovary 1-loculed. There is one ovule in it. The calyx of spiny vegetables develops into horny protuberances. Sowing with "seed" is actually fruit. Female flowers are clustered in leaf axils, with 6-20 florets per axil. Without a flower stalk, or with a flower stalk of varying length.

④ leaves. Before bolting, the leaves of spinach were born on the shortened stems, and the roots came out of the leaves. There are two types of leaves: round leaves and pointed leaves. Round spinach leaves are large and fleshy, smooth, ovoid or facing; pointed spinach leaves are narrow and thin, hastate or arrow-shaped, apex acute or obtuse. Spinach has dark green leaves, soft texture and slender petiole, which is the main edible part.

⑤ fruits and seeds. The fruit of spinach is a utricle, irregularly round, with 1 seed in it, wrapped in a hard leathery exocarp. It is divided into two types: thorn and non-thorn. The endocarp is corked, the thick-walled cells are well developed, and the water and air are not easy to penetrate, so the seeds germinate slowly. The 1000-grain weight of seeds is 9.5-12.599. Under general storage conditions, the seeds can be preserved for 3-5 years, and the seeds with 2-year-old have strong germination ability.

2. Requirements for environmental conditions

① temperature. Spinach is a kind of vegetable with the strongest cold tolerance among green leafy vegetables. It can survive the winter in the open field in the south of the Yangtze River basin, and it can survive the winter safely in the open field in the area of-10 degrees. North China, Northeast China and Northwest China can survive the winter in the open field with wind barrier and ground cover. The cold tolerance of spinach is closely related to plant growth and development and seedling age. For the plants with 4-6 leaves, the persistent roots can withstand the short-term low temperature of-30 degrees, and only the outer leaves are frozen and yellowed at the low temperature of-40 degrees, but the roots and buds will not be harmed. If the seedlings have only 1 or 2 leaves, or the seedlings are too large, or the plants that are about to bolt, it is easy to die from freezing injury during overwintering. Spinach has a wide adaptability, the suitable temperature for growth is 15-30 degrees, the optimum temperature is 15-20 degrees, spinach seeds can germinate at 4 degrees, the optimum temperature is 15-20 degrees, 4 days can germinate, the germination rate is more than 90%. With the increase of temperature, the germination rate decreased.

② illumination. Although spinach is a low-temperature long-day crop. However, flower bud differentiation is mainly affected by the length of sunshine, which is easy to pass through the light stage under long sunshine and high temperature, and low temperature can promote flower bud differentiation under long sunshine. After flower bud differentiation, the temperature increased and the bolting and flowering accelerated when the sunshine was longer. When the overwintering spinach enters the following spring and summer, the plant will bolt and blossom quickly.

③ moisture. Spinach has the most vigorous growth, thick leaves, good quality and high yield under the environmental conditions of 80%-90% air humidity and 70%-80% soil moisture. Spinach needs a lot of water in the growth process, lack of water during the growth period, slow growth, aging mesophyll, increased fiber, prone to downy mildew, especially in high temperature, dry, long sunshine, will promote flower organ development and early bolting.

④ soil nutrition. Spinach has a wide adaptability to soil, and it is suitable to be planted in water conservation, fertilizer conservation, moist (night tide) fertile soil, pH 6: 7.5 neutral or slightly alkaline loam. Acidic soil will poison spinach and is not suitable for cultivation. Spinach fast-growing green leafy vegetables require more nitrogen fertilizer to promote leaf growth, good quality and high yield. Nitrogen fertilizer should be applied on the basis of total nitrogen, phosphorus and potassium fertilizer.

3. Growth and development

The vegetative growth period of ①. From spinach sowing and emergence to growing all the differentiated leaves, the inflorescence began to differentiate from cotyledons to the appearance of two true leaves, which grew slowly. After the two true leaves unfolded, the number, weight and surface of leaves. Growing rapidly at the same time. The number of leaves during inflorescence differentiation varied with variety, sowing date and climatic conditions, ranging from 5 to 6 leaves to more than 20 leaves.

The reproductive period of ②. From inflorescence differentiation to seed maturity, there is a period of overlap between the early stage and the vegetative growth period. The factors that can enhance photosynthesis and nutrition accumulation in external conditions can generally promote the female to strengthen, with more lateral branches, more flowers and full grains after bolting.

Types and varieties of spinach

According to the shape of spinach leaves and the presence or absence of thorns on the fruit, spinach can be divided into sharp leaves (prickly) and round leaves (no thorns).

① Beijing pointed leaf spinach. Beijing local varieties. The leaf is arrowhead-shaped, there are a pair of deep lobes at the base, the green is thinner to the meat, the fiber is less, the quality is better. The fruit is diamond-shaped and spiny. It is cold-resistant and heat-resistant, with a yield of 1000-2500 kg per mu, which is suitable for root stubble overwintering and autumn cultivation.

② Japanese big leaf spinach. Leaf blade elliptic to ovoid, apex slightly pointed, base shallowly notched. The leaves are broad and fleshy, thick green. Strong heat resistance, not cold-resistant, suitable for summer and autumn cultivation. High output and good quality.

③ round leaf spinach. Introduced from the United States, it is a thornless species. The leaf is oval to broad triangular, the leaf is hypertrophy, the leaf surface is wrinkled, and the color is dark green. Sweet and tender quality, late bolting in spring, high yield, good quality, but not cold-resistant, single plant weight 0.5 kg. The disadvantage is the weak ability to resist downy mildew and virus disease. It is cultivated in Northeast, North China and Northwest.

Four Seasons cultivation techniques of spinach

Spinach is an important vegetable for stubble because of its wide adaptability, short growth period, rapid growth and rapid ripening. Products, big or small, are edible, and there are cold-and heat-resistant varieties. Cultivation methods include overwintering, burying head, spring spinach, summer spinach, autumn spinach, frozen spinach and so on.

1. Key points of cultivation techniques of spring spinach

The cultivation time of ① is from the first ten days of March to the middle of April and the first and middle of May.

② variety selection and sowing date. Spinach varieties with round leaves with late bolting and hypertrophic leaves should be selected for planting spring spinach. In early spring, when the surface layer of the soil is thawed by 4cm to 6cm, it should be sowed as early as possible, and it is better to sow with "Dingling sowing". According to meteorological data, the seeds can be sown when the daily average temperature rises to 4: 5 ℃. Generally, it is appropriate to sow seeds in early March and until mid-April. Because the early temperature of spring spinach sowing is low and the emergence is slow, which is not conducive to the differentiation of leaf primordium; in the later stage, the temperature rises and the sunshine is prolonged, which is beneficial to bolting and flowering, so the vegetative growth period is short, the number of leaves is small, it is easy to bolt, and the yield is low.

③ prepares the ground. Plots for growing spring spinach should choose plots that have not planted cruciferous vegetables or other field crops in the previous crop. Use rotten ring fertilizer as base fertilizer, add 30 kg of nitrogen and potash fertilizer, and then shallow ploughing to make a flat bed about 1.3 meters wide for sowing. Some made the beds in the first year and sandwiched the wind barrier for broadcast.

Sow seeds on ④. The method of soaking seeds to promote germination is often used in production. The seeds are soaked in warm water for 5 hours for 6 hours, then removed and put into germination at the temperature of 15: 20 ℃. After washing with warm water once a day, the seeds can sprout in 3 to 4 days. Generally adopt the method of sowing, the growth period of spring spinach is short, the plant is smaller, and the sowing rate is increased to 5-7 kg per mu. When sowing in early spring, it is best to use wet sowing ("sowing in the water"), first fill the bottom water, wait for the water to seep and sow the seeds, and then cover the soil, about 1 cm thick. Because there is a loose soil cover on the border surface, it not only reduces the evaporation of soil water, but also has the function of heat preservation. The seeds can emerge earlier when they are in a warm, humid and well-ventilated environment.

⑤ field management. The early stage of spring spinach should be covered with plastic film for heat preservation, which can be directly covered on the border surface, and after emergence, the film can be removed or changed to a small arch shed, which will cover the day and night cover and rain cover, so that the seedlings can see more light. For spring spinach sown by wet sowing, due to sufficient soil moisture, the first water can be irrigated when the seedlings grow 2-3 true leaves. When watering the second water, 15 kg of urea per mu or 20 kg of nitrogen and potassium fertilizer per mu should be applied, especially 15 days before harvest. Watering is carried out according to the climate and soil moisture, and the principle is to keep the soil moist all the time.

⑥ harvested in good time. Generally, it can be harvested 40-60 days after sowing, and the harvest standard can be reached in the first and middle of May.

2. Cultivation techniques of summer spinach

Summer spinach, also known as "Fu spinach", is spinach on the market from July to August. The seedling growth period is in the season of high temperature and long daylight, although the leaf primordium differentiation is fast, but the flower bud differentiation and bolting is also fast. Moreover, the temperature is high, the evaporation is large, the respiration is exuberant, the plant nutrient accumulation is less, the growth of leaf area is limited, the quality is poor, and the yield is low. The cultivation of summer spinach should focus on solving the problems of seedling emergence, seedling protection and robust growth. The main points of cultivation are:

① cultivation time. The seeds were sown from the first and middle of June to July, and harvested about 50 days after sowing.

② variety selection. Summer spinach should choose varieties with strong heat resistance, rapid growth, bolting resistance, disease resistance, high yield and good quality. The varieties suitable for summer planting are Dutch Bijiu No. 5 spinach F1, K5, Japan Beifeng, Shaoxing spinach and so on. Secondly, Guangdong round-leaf spinach, Nanjing big-leaf spinach, Huacheng No. 1 and so on can be used.

③ determined the suitable sowing date. The sowing date can be arranged more than 50 days before the planned listing. At the same time, it is necessary to arrange as far as possible to sow seeds before the highest temperature in summer, so that the seedlings will grow for a period of time and then enter the high temperature period, which is beneficial to obtain higher yield. Therefore, the suitable sowing time of summer spinach is the first and middle of June.

Seeds were soaked in ④ to accelerate germination. Summer spinach must be soaked at low temperature to accelerate germination before sowing. The method is as follows: soak in well water for 24 hours, wrap it with gauze, hang it in the well about 20 cm above the surface of the water, wash the seeds once a day, and wait for the radicles of the seeds to be exposed 2-3 days later. Soaked seeds can also be spread out in a cool indoor place to promote germination, pay attention to turn and maintain a certain amount of moisture, after 5-6 days can also sprout. Or the soaked seeds were put under 15 ℃ ~ 20 ℃ to accelerate germination, and the seeds could sprout in 3 ~ 4 days.

⑤ soil preparation, fertilizing and sowing. Before cultivated land, 2000-3000 kg of mature farm manure, 20 kg of three-element compound fertilizer and 10 kg of urea should be applied every 667 square meters. 1.5 kg of zinc fertilizer and 0.7 kg of boron fertilizer should also be applied as base fertilizer. Shallow ploughing Harrow, made into 1.1 meters wide flat border (including ridges), the border surface must be flat, the border should not be too long, about 15 meters is appropriate. Sow seeds before 10:00 in the morning and after 4 p.m. That is, first water, wait for the water to seep down, sow seeds and cover 1.5 cm of fine soil. In order to ensure a sufficient number of seedlings, the sowing rate can be increased to 8 kilograms per 667 square meters. After sowing, cover the border with crop straw to cool and moisturize, prevent heavy rain erosion, and ensure that the seedlings are uniform. Try not to water before emergence, so as not to harden the soil or wash off the cover soil when watering, so that the seeds are exposed and affect the emergence of seedlings. Remove the mulch in the evening or morning after emergence.

⑥ field management.

A, Jianmiao. After emergence, the seedling should be carried out in the place where the seedling is too dense.

B, watering. Fertilization and irrigation during the growth of summer spinach should be based on the principle of light watering and frequent watering. When watering for the first time, the flow should be slow and the amount of water should be small, so as not to cause dead seedlings after the cotyledons are soaked in mud. Water is usually watered once every 5-7 days to keep the soil moist to reduce the ground temperature. Watering time should be in the early morning or evening, to water wells, not pits and ponds and rivers. During the growth of seedlings, they do not like high temperature and strong light, and can set up a shed for shade if necessary. The mulch is covered early and uncovered late, which can cool down and protect against rain.

⑦ controls diseases and insect pests. The main diseases of summer spinach are quenching, downy mildew, anthrax and virus. Prevention and treatment of quenching disease: after spinach emergence, the ground and plants can be sprayed with 3000 times of Luheng No. 1 or 1500 times of gram bacteria. If the disease is more serious, you can use 72.2% Pulick 600x liquid plus 68.75% Dupan Yibao 1000 times liquid spray. Methods for prevention and control of downy mildew: 72% manganese zinc downy urea 600 times, or 58% metalaxyl wettable powder 500 times, or 64% antivirus alum manganese zinc wettable powder 500 times, or 40% ethyl phosphorus aluminum wettable powder 200 times, alternately sprayed twice every 7 days. Methods for prevention and control of anthracnose: 1000 times of thiophanate methyl, or 600x of carbendazim wettable powder, or 500x of mancozeb wettable powder, were sprayed alternately for 2 times every 7 days. It is best to compound control according to different chemical characteristics. Virus disease prevention and control methods: eliminate aphids as soon as possible to reduce the chance of virus transmission. The prevention of leaf miner pests should be strengthened.

3. Cultivation techniques of summer spinach in greenhouse.

Spinach is an important green leafy vegetable with strong cold tolerance. Spinach is widely cultivated in autumn, winter and spring. It is very difficult to grow spinach in high temperature and rainy summer. During the idle period of winter warm greenhouse and arch greenhouse in summer, we experimented with the method of shelter from rain, and achieved success. The yield per mu can reach more than 1500 kg, the market prospect is good, the income is very considerable, and one crop can be harvested in about 40 days. The main technical measures taken to grow over-summer spinach are as follows:

① protection facility. The spinach sown from May to July belongs to over-summer spinach, which needs to be sheltered from the sun and rain when planting over-summer spinach.

A, cover the sunshade net. The solar greenhouse (warm winter greenhouse) can be used to cover the sunshade net on the film to achieve the purpose of shading and blocking rain during the summer rest period, and the large arch greenhouse can also be used to cover the shading net on the film to cool down. It is best to use a shade net with a shading rate of 60%. When installing the sunshade net, it is best to leave the greenhouse film 20 cm (the cooling effect is remarkable), and the roll is convenient. During the high temperature period from 9 am to 4 pm on a sunny day, the greenhouse and greenhouse are covered with a sunshade net to prevent direct sunlight, and when the light is weak before 9 am and after 4 pm on a rainy or sunny day, roll up the sunshade net, which can not only prevent the strong light from high temperature, but also let the spinach see enough sunshine.

B, add anti-insect net. Aphids and gray planthopper are the vectors of virus disease. preventing these vectors from entering the greenhouse is one of the main technical measures for planting summer vegetables. Before planting, it can be around the arch shed or to the south of the greenhouse. Seal 60-70 purpose anti-insect net, so that it not only does not affect ventilation, but also securely isolates the virus transmission vector into the greenhouse. The greenhouse film should also be inspected and repaired in time to prevent Rain Water from entering the shed and causing virus disease.

C. In a word, taking measures to shelter the sun and rain is the key to the cultivation of spinach over summer.

Heat-resistant varieties were selected for ②. More heat-resistant varieties should be selected. at present, K4, K5, K6, K7 and other varieties produced by Bijiu Company of the Netherlands are mostly selected, and Sheng Pioneer also performs very well. Their common characteristics are heat resistance, disease resistance, bolting resistance, fast growth and high yield.

③ cultivation method. When the soil in the solar greenhouse or large arch shed is sandy loam, it can be planted on the border because it is easy to infiltrate or evaporate. the general width of the border is 1.5 meters, of which the width of the border is 1.15 meters, the width of the ridge is 35 centimeters, the width of each border is 9 rows, the row spacing is 12 centimeters, the plant spacing is 2.50 centimeters, and the seed used per mu is about 1.75 kilograms. When the soil in the greenhouse is clayey, it is best to use ridging cultivation because the soil moisture is not easy to seep or evaporate. Practice has proved that spinach is most afraid of moisture in summer, such as stem rot in the border and good ventilation at the base of the leaves cultivated on the ridge. it's not easy to get sick. Generally 50 cm from a ridge, each ridge planting 2 rows, hole distance 5 cm, each point 2, general mu with about 1 kg.

④ fertilizer and water management. Spinach likes fertile, moist, high organic matter content soil, such as growing summer spinach in solar greenhouse, because of the fertile soil, generally no longer apply base fertilizer; such as in the new greenhouse or new arch shed where the soil is not fertile, about 3 square meters of fully mature chicken manure can be used as base fertilizer per mu. Topdressing is best with potassium nitrate or potassium sulfate compound fertilizer, sandy soil is divided into three times to apply potassium nitrate 15kg or potassium sulfate compound fertilizer 30kg, with water application, according to the growth of spinach should be less before and more after. Clayey loam is divided into 3 times to apply 12 kg of potassium nitrate or 25 kg of potassium sulfate compound fertilizer. In summer, water should be watered at the right time, and after watering, the hoe can not only moisturize but also prevent the growth of moss, which is the key to disease prevention. Especially the paddling hoe just after emergence is very important. If the ground is covered with moss, spinach will have serious dead seedlings and rotten leaves.

⑤ pest control. Oversummer spinach is prone to diseases such as quenching disease, downy mildew, bacterial rot and insect pests such as whitefly and Liriomyza huidobrensis. Generally, 600 times of Dasheng + 600 times of aldicarb was sprayed once on the fifth day after sowing (just coming out of the whole seedling), once again on the 12th day, 600 times of Kelu + avermectin + agricultural streptomycin on the 20th and 28th days, and once on the 35th day, so as to control the occurrence of the disease. Prevent virus diseases, pay attention to pest control, and prevent insect transmission. We should also pay attention to shading and cooling, prevent rain from excessive drought, and increase the application of organic fertilizer, potash fertilizer and micro-fertilizer. Spraying phytopathogen, virus An and so on every 7 days can prevent virus disease.

⑥ harvest. When spinach grows to 20-30 cm high (about 40 days), it should be harvested in time. It can also be harvested 1-2 days earlier or later according to the market price. But don't wait too long, because spinach is easy to rot in summer, so the harvest time is better early than late.

4. Cultivation techniques of spinach in early autumn.

Spinach is planted in early autumn, the growing period is about 30 murals for 40 days, the time is short, and the vegetables are on the market quickly, which can meet the market demand for autumn light vegetables and achieve higher economic benefits.

① cultivation time. It will be sown around August 20 and will be on the market around mid-late September.

② chooses the variety. Just entering autumn, the temperature is still very high (commonly known as "autumn tiger"). When sowing spinach, we should choose varieties that are heat-resistant and easy to germinate, such as omnipotent spinach and so on.

Treatment of ⑤ before harvest and frozen storage. Frozen storage needs timely harvest to make spinach freeze quickly, in a dormant state with very low physiological activity, and reduce loss. Harvest early, the external temperature is still high, can not go into the ditch frozen storage, the vegetable body respiration is exuberant, easy to heat in the heap, so that the leaves cover yellow, rot, increased loss; late, spinach frozen in the ground, difficult to shovel. The harvest season should be observed in the field, so as to see the spinach leaves frozen in the morning and thaw during the day as the harvest time. It is usually in the middle to late November. However, when the leaves are frozen, do not shovel them immediately. They should be harvested when there is no dew bead white frost in the leaves after thawing. Because it is difficult to defrost and perish when the leaves are frozen; water droplets will increase the humidity of the vegetables when they are harvested, and they are easy to rot when pre-stored. During harvest, the spinach can be shoveled with a shovel, leaving red roots 2-3cm, shaking the soil, putting it on the ground into large bundles of diameter 30-40cm, with the roots facing up, and the leaves close to the ground, so as to keep the leaves from losing water, handstand in the shady and flattened border behind the wind barrier, leave the bundles in two lines and store them in advance for 45 days. The size of the bundles should be appropriate, if the bundles are too large, the center of the vegetables will not freeze through, and the heat released by respiration of the vegetables can not be lost, resulting in yellow, deterioration or even decay of the leaves; if the bundles are too small, they are easy to be drained by the wind, increase the loss, and affect the yield and quality of the products. During pre-storage, cover Reed curtain during the day to avoid wilting caused by water evaporation caused by sunlight. Pre-storage time depends on the climate, such as spinach harvest temperature has dropped significantly, a little dry can be frozen, if the weather turns warm, do not freeze, can be stored for a few days, so as to avoid heat and rot of the vegetable pile after frozen storage.

⑥ digging trenches and burying. Spinach should be frozen in shaded, cool, well-ventilated places, such as behind the wind barrier, using the natural low temperature in winter for storage. The optimum storage conditions are: the temperature is-4 ℃, and the air relative humidity is 90% Mel 95%. The storage place should be prepared in advance, and the form of cellar varies from region to region. Storage method: first, make a parallel border at the 20cm behind the wind barrier, the width of the border is 80-150cm, and the spinach is pre-stored in the border, with the roots facing up and the leaves facing down. When burying, straighten the bundles, put the roots down and leaves up in the same place, code into 2 or 4 lines, leave a l0cm gap between the rows, take soil from outside the border and fill it in the space between the bundles of vegetables, then surround the bundles with soil, and finally cover it with a thin layer of soil, which is about 5cm thick, which can protect against wind and moisture, prevent leaves from being attacked by cold wind and protect against the sun. The upper part of the vegetable Bale freezes quickly after it is covered with soil. With the decrease of temperature, the vegetable Bale freezes from the top to the bottom. When it freezes to the middle waist of the vegetable Bale, the second time the soil is covered with 10cm, and then the soil is covered again, the total thickness of the soil is about 25cm. When the temperature is colder, you still need to cover the soil or cover it with grass curtains.

⑦ unfrozen on the market. Generally from December to the end of February of the following year, the frozen spinach bundles are dug out before the new spinach is listed on the market, and then refrozen and refurbished and listed on the market. Thawing method: do not hurt the bundles when ploughing the frozen soil, do not damage the leaves when moving, avoid causing mechanical damage, hold the roots of the bundles with both hands, put them on the trolley, and transport them to the vegetable cellar or cold house with lower temperature, room temperature is generally 0 ℃, humidity should be large, let the frozen spinach thaw slowly, not too quickly. During thawing, the ice crystals in the intercellular space of spinach leaves will gradually melt and return to the leaf cells, and the leaves will return to their original fresh and tender state and will not affect the product quality. After 5 days of thawing, open the bundles and repair them in time, remove the yellowing and rotten leaves, cut off the main roots, break them into small bundles about 1kg, wash them and put them on the market in baskets.