The Latest Winter Spinach Cultivation Techniques and Methods Tutorial

Spinach originated in Iran and was introduced to China from Nepal during the reign of Emperor Taizong of Tang. It is now one of the vegetables we commonly cultivate. Spinach can be divided by sowing time into spring spinach, summer spinach, autumn spinach and winter spinach. Winter spinach refers to spinach sown from mid-October to early November each year and harvested around the Spring Equinox of the following year. The arrival of winter spinach on the market can effectively fill a gap in the market, and its cultivation value is relatively high. So how should this winter spinach be grown? Qinnong Web will introduce it to you next: the cultivation techniques for winter spinach.

1. Choosing varieties

Because winter spinach needs to grow throughout the entire winter, varieties with strong overwintering ability, strong cold resistance, good quality, fast growth and high yield potential should be selected. Ordinary spinach varieties tend to bolt during the overwintering period, reducing yield and quality and affecting the value of the spinach.

2. Land preparation

After the previous crop is harvested, remove the stubble promptly. Then each mu of land needs 5000 kg of decomposed organic fertilizer and 50-60 kg of ternary compound fertilizer, with deep ploughing of more than 25 cm, after which flat beds 1.2 m to 1.5 m wide are formed.

3. Sowing

The choice of sowing time is very important. Practice has shown that spinach is relatively safe during the overwintering period when it has 4-5 leaves, so sowing from late September to early October is appropriate. Spinach seeds germinate slowly. To shorten the emergence period, the seeds can be soaked in 20°C warm water for 12 hours the day before sowing, then removed, briefly air-dried and sown. If sowing is later, 4-5 days before sowing the seeds can be soaked in cold water for 12-24 hours, taken out and piled indoors at a thickness of about 15 cm, covered with gunny sacks to keep warm, and turned once a day so that the temperature and humidity within the pile are even, with the temperature kept at around 20°C. After 3-4 days, when more than 60% of the seeds show radicles, they can be sown. Coated seeds do not need soaking or germination. There are two sowing methods: dry sowing and wet sowing. Dry sowing means sowing and pressing first, then watering; wet sowing means watering before sowing, then sowing after the water has seeped down, and covering with soil after sowing. Seeds that have been germinated must be wet-sown. Sowing methods include broadcasting and drilling. Drilling requires sufficient subsoil moisture; when broadcasting, the seeds should be spread evenly, then covered with about 2 cm of soil. Generally, the seeding rate per mu is 4-5 kg, increased appropriately for late sowing. In addition, the sowing time of winter spinach also directly affects the overwintering ability of the seedlings, the harvest time and the yield.

4. Routine management

The routine management of winter spinach mainly targets three periods of winter spinach, including seedling-stage management, overwintering-stage management and green-returning vigorous-growth-stage management. The management methods required differ by period. Qinnong Web will now introduce them specifically.

1. Seedling-stage management: After sowing, if the soil is dry, a light watering can be given. When the moisture condition is suitable, shallowly hoe the bed surface to loosen the topsoil and facilitate emergence. When 1-2 true leaves have emerged, keep the soil moist; at 3-4 true leaves, water can be appropriately controlled to promote root development and facilitate overwintering. If the seedlings are too dense, thin them once at 2-3 true leaves, with a spacing of 3-5 cm. If aphids cause damage, spray pesticide for control.

2. Overwintering-stage management: From when spinach stops growing until before it turns green again the following spring is the overwintering period. To prevent cold and drought damage, a freezing water can be applied before the soil freezes; where fertilizer is insufficient, urine water can be mixed in. After the soil freezes, horse manure or barnyard manure can be spread to protect the seedlings through winter. Before the plants turn green again, choose clear warm weather, and after the frost has melted, sprinkle fresh urine, 1000-2000 kg per mu, finishing by 3-4 p.m.

3. Green-returning vigorous-growth-stage management: In early March of the following year, spinach begins to turn green and grow. Because the temperature is still low at this time, if the moisture condition is good, watering can be temporarily withheld and hoeing used to conserve moisture; if the moisture condition is poor and the temperature rises quickly, one watering can be given, with the amount preferably small rather than large. However, saline-alkali land can be watered appropriately to leach salts. Windbreak beds and sandy loam warm up quickly and should be watered appropriately earlier. After spinach begins vigorous growth, its demand for fertilizer and water surges. During this period the soil should be kept moist and not allowed to dry out, and topdressing and watering should be carried out promptly to promote vegetative growth and delay the bolting period. Generally, 15-20 kg of urea is applied per mu. Water after fertilizing; with sufficient fertilizer and water, spinach grows quickly and can be harvested in 10-15 days. Adopting windbreaks and flat film mulching (mulching for 7-10 days) in early spring can achieve the goals of an earlier market launch and high yield.

5. Pest and disease control

The main pests and diseases affecting winter spinach include downy mildew, anthracnose, viral disease and aphids. Downy mildew and anthracnose can be sprayed for control in the early stages of the disease with 75% chlorothalonil 600x solution, 25% metalaxyl 700-800x solution or 40% fosetyl-aluminium wettable powder 200-300x solution. For viral disease, in addition to practising crop rotation, aphids and other virus-transmitting vectors should be controlled promptly. Aphids can be controlled with agents such as imidacloprid.

6. Timely harvesting

Generally, once the seedlings are more than 10 cm tall they can be harvested in batches. About 15 days before a one-time harvest, 15-20 mg/kg of 920 can be sprayed on the leaves, together with additional urea or ammonium sulphate, to allow earlier harvesting and increase yield.

7. Seed saving

Spinach grown for seed can be sown slightly later than winter spinach. Drill it, with a row spacing of 20-23 cm. After the plants turn green in spring, successively pull out off-type plants and early-bolting male plants, leaving some vegetative male plants, so that the plant spacing reaches about 20 cm. During the bolting period, do not irrigate too much, to avoid thin, weak and lodging flower stalks that reduce seed yield. After flowering, topdress, irrigate and spray the leaves with a 1%-2% clarified calcium superphosphate solution to make the seeds plump. After the male plants set seed, pull out the male plants to improve ventilation and light penetration. Harvest when most of the stems and leaves have withered and yellowed and the seeds are ripe, then after-ripen for several days before threshing.

The above is the introduction to winter spinach cultivation techniques brought to you by Qinnong Web. From the above, it can be seen that among the winter spinach cultivation techniques, the most critical step is the sowing time, which is also the key point farmers should pay attention to.