Where are the walnut-producing areas in China? What are the cultivation techniques?

Walnut, together with hazelnut, almond and cashew, is known as one of the world's four major dried nuts. China is the distribution center of the genus Juglans and also the place of origin of the walnut, with a cultivation history of more than 7000 years. So where are the walnut-producing areas in China? What are the cultivation techniques?

I. Where are the walnut-producing areas?

1. Walnut-producing areas

The walnut-producing areas in China are mainly concentrated in Xinjiang, Hebei, Sichuan, Yunnan and other regions.

The main production areas for Sichuan walnut cultivation are the Western Sichuan Plateau, the Qinba Mountains, the central Sichuan hilly region, the Sichuan Basin and other areas. The Xinjiang walnut production areas are mainly distributed in Aksu Prefecture, Hotan Prefecture and Kashgar Prefecture.

2. Growing environment for walnut

(1) Temperature

Walnut is a warmth-loving tree species. The suitable temperature range for growth and the frost-free period are: annual average temperature 9°C-16°C, extreme minimum temperature -25°C, extreme maximum temperature below 38°C, and a frost period of less than 150 days.

(2) Light

Walnut loves light, and after entering the fruiting stage it needs even more sufficient light conditions. The annual sunshine hours must be above 2000 hours to ensure the normal growth and development of walnut; if below 1000 hours, both the shell and the kernel develop poorly.

(3) Soil

Walnut prefers loose soil texture and good drainage, and grows poorly on soil with too high a groundwater level or heavy clay. It grows best on calcium-containing slightly alkaline soil. Its range of adaptation to soil pH is 6-8, which affects growth and fruiting. Walnut loves fertilizer and requires fertile soil with high organic matter content.

(4) Water

Walnut tolerates dry air but is relatively sensitive to soil moisture conditions; soil that is too dry or too wet is unfavorable to the growth and fruiting of walnut. Therefore, mountain walnut orchards need soil and water conservation engineering measures, while on flat land the drainage problem must be solved. For further guidance, please consult your local agricultural department.

II. What are the cultivation techniques for walnut?

1. Site selection and cultivation

Walnut is suitable for growing on warm, deep, well-drained sandy loam and black soil, and should be planted on sunny slopes and in sheltered spots. Newly planted young trees need sufficient water and fertilizer, and should be sprayed with new high-fat film, which can ensure above-ground water evaporation and seedling water transpiration, isolate pests and diseases, shorten the seedling recovery period, and accelerate root development.

2. Shaping and pruning

To make walnut bear fruit earlier, with high and stable yields, reasonable shaping and pruning is a very important cultivation technique. The pruning period for walnut differs from that of ordinary fruit trees: it is done after the fruit is harvested and before the leaves turn yellow, and a healing and antiseptic film should be applied promptly to the pruning wounds to promote wound healing and prevent invasion and infection by pathogens.

3. Stabilizing flowers and setting fruit

At the bud stage, young fruit stage and fruit swelling stage respectively, spray fruit-stalk strengthening agent to thicken the fruit stalk, increase the amount of nutrient transport, prevent flower drop, improve pollination capacity, increase the fruit-setting rate, accelerate the swelling speed, and ensure high-quality and high-yield fruit. The alternate bearing of the tree, with large and small years, causes an imbalance in the tree's load, which affects both balanced returns and orchard tree health. During the flower bud differentiation period each year, brush Flower Promoter No. 2 once around the trunk, which can promote flower bud differentiation, suppress the rampant growth of summer shoots, strengthen flowers, and improve pollination capacity and the fruit-setting rate.

4. Pest and disease control

The main insect pests of walnut are: walnut saturniid moth, walnut stub-winged moth, and walnut fruit weevil. The main diseases of walnut are: walnut black spot disease and walnut branch blight. The control measure is to spray targeted pesticides to kill them. At the same time, spray the tree with Tree Guard General and spray the orchard with new high-fat film to keep it warm and preserve soil moisture, ensuring safe overwintering.

Warm reminder: In summary, the selection of walnut cultivars and cultivation methods has its specific requirements. To fundamentally improve the survival rate of seedlings, every step must be strictly carried out, and cultivation and management must be done reasonably and scientifically.