Key Technical Points for Protected Cultivation of Leafy Goji (Vegetable Goji)

Every 100 grams of tender stems and leaves of goji contains 5.8 grams of protein, 1.0 grams of fat, 6.0 grams of sugar, 3.96 milligrams of carotene, 0.23 grams of thiamine, 1.1 milligrams of nicotinic acid, and 3.0 milligrams of vitamin C. Regular consumption has health benefits such as improving eyesight, nourishing yin and moistening the lungs, enhancing immune function, and anti-aging. Consumers in southern China are accustomed to using goji tender stems and leaves in soups or stir-fries, and there is considerable demand in some cities; Guangzhou alone has an annual output of about 70,000 tons. Introducing vegetable goji for protected cultivation in the north can both enrich the variety of vegetables and increase the economic returns of vegetable growers, making it a vegetable with considerable development prospects.

Vegetable goji mainly has two varieties: thin-leaf goji and large-leaf goji. Thin-leaf goji has ovate-lanceolate leaves with thicker leaf flesh and a stronger flavor; large-leaf goji has ovate leaves with thinner leaf flesh and a milder flavor, but higher yield. Either variety can be selected for production.

Goji is mostly propagated by cuttings in production. One-year-old branches should be selected for cuttings. When taking cuttings, cut 8-10 cm lengths from the base of the branch, each segment must have 3-5 axillary buds, and the cutting diameter should be about 5 mm. Soaking the cuttings in a 50 mg/kg ATP rooting powder solution for 24 hours helps the cuttings take root. In production, cuttings can be inserted directly into the cultivation bed, or inserted into a seedbed and transplanted after rooting. After inserting the cuttings, water thoroughly, and promptly set up a small arched shed covered with plastic film to retain moisture. On sunny days, add a shade net, keep the bed temperature at 20-25°C and soil moisture at about 20%. After 10-15 days, adventitious roots grow from the base and middle of the cuttings, and new buds sprout from the upper part. If new buds sprout from the upper part of the cutting but no adventitious roots grow from the lower part, this is false rooting. This phenomenon generally occurs when soil temperature is low and air temperature is high. In production, measures such as raising soil temperature, lowering air temperature, and maintaining suitable humidity in the cutting bed should be taken to promote early rooting and survival of the cuttings. Under normal conditions, the survival rate of goji cuttings generally reaches over 90%.

Goji is suitable for various soils, but fertile sandy loam is more favorable for growth. Before planting, plow the soil deeply, and apply 2000-2500 kg of organic fertilizer and 50 kg of ternary compound fertilizer per 667 sq m. In a high-efficiency energy-saving solar greenhouse, flat beds running north-south must be made, with a bed surface width of 1.5 m. Planting row spacing is 26 cm, plant spacing is 15 cm, or both plant and row spacing are 20 cm; plant in furrows at a planting depth of 6-7 cm. After planting, water thoroughly. To bring the product to market around the Spring Festival, the planting period should not be later than mid-October.

After planting, 40-50 days later, new branches can reach 20-30 cm. At this time, cultivate the soil and apply 15 kg of ammonium sulfate per 667 sq m, or spray 0.3% monopotassium phosphate as a foliar fertilizer. Keep the indoor temperature between 15-25°C and keep the soil moist. As the outdoor temperature drops, avoid heavy irrigation, so as not to lower soil temperature and affect goji growth. After the first harvest, apply quick-acting chemical fertilizer once every 10-15 days until the final harvest. Each September, apply expanded chicken manure or other organic fertilizer between the rows as a supplement.

The products of protected cultivation of vegetable goji in the north come to market from mid-December to mid-to-late May. Mainly pick 15-20 cm tender shoot tips, and 667 sq m can yield 2000-2500 kg. After harvesting the tender shoots, the axillary buds at the base can produce new tender branches again. When harvesting, special care should be taken to leave enough 3-6 basal axillary buds to facilitate the sprouting of more new branches. In mid-to-late May, as the temperature rises, branches used for propagation should stop being harvested, and maintenance management should be carried out to cultivate robust branches in preparation for propagation in mid-to-late September. The old roots from which cuttings were taken are still used as mother plants to produce goji tender shoots. Using old roots to produce goji tender shoots in protected cultivation brings the product to market earlier and yields higher. Old roots can be used continuously for 2-3 years, after which they must be renewed.

In protected cultivation of vegetable goji in the north, attention must be paid to the prevention of pests and diseases. Cuttings introduced from the south must be healthy branches free of pests and diseases. Before being cut into cuttings, the branches should be soaked in a disinfectant solution, so as to avoid carrying residual goji psyllids and goji gall mites on the branches into the protected facility. In the same solar greenhouse, it is best not to mix-plant other vegetables. Before covering the solar greenhouse with film, clean the environment thoroughly and remove weeds and fallen leaves. After covering with film, fumigate with chlorothalonil smoke agent to maintain a clean ecological environment. After cutting propagation and planting, install insect-proof nets at the ventilation openings of the solar greenhouse. In addition, temperature and humidity management in the greenhouse should be strengthened to keep the goji growing robustly.