How to Grow Spinach in a Greenhouse? Latest Cultivation Techniques and Methods Tutorial
Spinach is one of the most common vegetables, also known as Persian spinach, spinacia, spinate, parrot vegetable, red-root vegetable, flying dragon vegetable, etc. It is an annual herbaceous plant of the genus Spinacia in the Amaranthaceae family, native to Iran, and now found all over the world. It is widely cultivated throughout China and has extremely high cultivation value. Let us take a look at greenhouse spinach cultivation techniques below!
Cultivation Environment
Spinach is a cold-tolerant vegetable. The seeds can germinate at 4°C, with the optimum being 15-20°C. The suitable temperature for vegetative growth is 15-20°C. Growth is poor above 25°C. The aboveground parts can withstand low temperatures of minus 6-8°C. It has low requirements for sunlight intensity and relatively high water requirements. With sufficient water, the leaves are thick during vigorous growth, the yield is high, and the quality is good. It has strong adaptability to soil, but fertile soil with strong water and fertilizer retention capacity is still preferable. It is not tolerant of acid, with a suitable pH of 7.3-8.2, and requires more nitrogen fertilizer and appropriate phosphorus and potassium fertilizer.
Choosing Varieties
Spinach can be divided by seed morphology into two varieties: prickly-seeded and smooth-seeded. The prickly-seeded type has rhombic, prickly fruits, with smaller and thinner leaves that are halberd-shaped or arrow-shaped. Because of its soft texture and low astringency, it is suitable for eating (pointed-leaf type). It has relatively strong cold and heat tolerance, is early-maturing, and bolts early. The smooth-seeded type has irregularly round, spineless fruits, with large, wrinkled, ovate, elliptical, or irregular leaves, short petioles, relatively weak heat tolerance, and later bolting, making it suitable for overwintering cultivation. During cultivation, varieties suitable for early spring greenhouse planting such as Boza 58, Boza 18, Quanneng, and Boza Guanneng can be selected.
Land Preparation and Fertilization
After the autumn vegetables are harvested, do not remove the greenhouse film. Directly carry out fertilization, land preparation, and bed making. Generally, apply 3-5 tons of high-quality fully decomposed farmyard manure per mu, 20-25 kg of diammonium phosphate, 10-15 kg of potassium sulfate, or 40-50 kg of 45% ternary compound fertilizer, and make flat beds 1-1.5 m wide.
Sprouting and Sowing
One day before sowing spinach seeds, soak the spinach seeds in cool water for about 12 hours. Rub off the mucus, remove and drain, then sow or sprout at 15-20°C. After 3-4 days, when most seeds have white sprouts showing, they can be sown. Generally, sowing is done in early December. When sowing, evenly scatter the seeds on the leveled bed surface, with a sowing depth of 1-1.5 cm, then tread over it again, and after treading, water thoroughly. Drilling is best. The row spacing is 8-10 cm. Generally, about 4 kg of pure seeds are sown per mu.