Suitable temperature, humidity and climate for growing grapes

Temperature

The minimum temperature required for grape growth is about 12℃-15℃, and the minimum ground temperature is about 10℃-13℃. The optimal temperature during the flowering period is about 20℃, and the fruit will expand. The optimal temperature during this period is 20℃-30℃. If the temperature difference between day and night is large, the coloring and sugar content will be better. Grapes after bud break in spring. If the temperature rises rapidly, it is easy to cause the branches to become elongated, with insufficient node length, and poor fertilization during the flowering period. If there is a cold spring, pay attention to applying more phosphorus fertilizers and high-carbon organic matter, and try to reduce nitrogen fertilizers.

Rainfall

Grapes have strong drought tolerance and can be cultivated in areas with annual rainfall of 350-1200 mm. The seasonal distribution of rainfall has a great impact on grape growth, fruit quality and yield. In spring, bud eyes germinate and new shoots grow. If there is sufficient rainfall, it is conducive to the continued differentiation of the inflorescence primitives and the growth of new shoots. The grape flowering period requires sunny, warm and relatively dry weather. If the weather is humid or continuous rainy and low temperatures, it will hinder normal flowering, pollination, and fertilization, causing the ovary and young fruits to fall off. Excessive rain or continuous rain during the grape ripening period (July-September) will cause a decrease in glucose content, the breeding of diseases, and fruit rot, which will have a particularly serious impact on grape quality. The late growth period of grapes (September-October) is very rainy, and the new shoots are not mature enough and are prone to freezing during the winter. Therefore, generally speaking, grapes are most suitable for cultivation in places with sufficient sunshine, loose soil, arid climate and irrigation conditions. In the case of excessive drought, the growth of grape branches and leaves is slow, the photosynthesis efficiency of the leaves is weakened, and the respiration is strengthened, which often leads to insufficient plant growth, reduced fruit sugar content, and increased acidity. Therefore, when developing grape production in arid areas, attention must be paid to the establishment of irrigation facilities.

Light

Grape is a typical light-loving crop. Under sufficient light conditions, the leaves will be thick and rich in color, the plant will grow robustly, the flower buds will be well differentiated, the yield will be high, and the fruit quality will be good. The opposite is true when there is insufficient light. Different grape varieties require different light intensity. Eurasian varieties require higher light conditions than American varieties. For example, varieties such as Camber can color well under scattered light conditions, while varieties such as Roselle, Rizamate, and Cabernet Sauvignon require direct light to color normally. The dried variety Seedless White has higher lighting requirements. high. Places that are too humid and poorly lit are not suitable for grape production.

Soil

Grapes do not have strict soil requirements. Except for places with heavy saline-alkali soil, swampland, groundwater level less than 1 meter, heavy soil and poor ventilation, grapes can be grown in various places. It can be cultivated on any type of soil, but the most suitable grapes are gravelly loam and sandy loam with loose soil and good ventilation. In particular, some varieties for preparing high-end wines have strict requirements on soil texture and structure. Grapes have a greater adaptability to soil pH, and can generally be cultivated with a soil pH of 5.8-8.2. Among them, grapes grow best when the soil pH is 6.5-7.5. Different grape varieties have different root system resistance to salt-alkali and iron-deficiency yellowing. Generally, European and Asian varieties are more resistant to salt-alkali, while European and American hybrid varieties are less resistant to salt-alkali and are prone to leaf yellowing on saline-alkali soils. symptoms. Chadian Township, Tianjin City, China, has achieved good results by utilizing the improved seaside saline-alkali land to develop Muscat grape production. But generally speaking, it is not suitable to plant grapes in places where the soil is too wet, heavy, and the soil is highly salinized.

Nutrition

Grapes are similar to most crops. There are about 17 kinds of nutrients required for their growth: carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, Sulfur, iron, manganese, zinc, copper, boron, molybdenum, chlorine, and cobalt. The carbon and oxygen in the base are obtained from carbon dioxide in the air during photosynthesis, and hydrogen comes from moisture in the soil. Except for nitrogen, most of the other elements Absorbed from the soil by the roots, their proportional relationship is: 94%-99.5% of the fresh tissue of the crop is composed of carbon, hydrogen and oxygen from air and water, while only about 0.5%-6% is from nutrients in the soil. . Chemical fertilizers mainly provide the three elements of nitrogen, phosphorus and potassium. Some chemical fertilizers also contain large amounts of calcium, magnesium and sulfur. Although the effect of using chemical fertilizers is obvious, excessive use can easily cause fertilizer damage, especially the amount of potassium fertilizer should be used carefully. Organic fertilizers have lower nutrient content, can be used in large quantities, and can improve the physical, chemical, and biological properties of the soil. In addition, soil amendments can be added depending on the soil condition. Generally speaking, strongly acidic soil is more likely to lack phosphorus, potassium, calcium, magnesium, silicon, molybdenum, zinc, copper, boron and other elements; alkaline or calcareous soil is more likely to be deficient in nitrogen. , phosphorus, iron, manganese, zinc, copper, iron and other elements. Nutrient supplementation is mostly done in three ways: base fertilizer, top dressing, and foliar fertilization. The base fertilizer is used after hibernation or harvest. Top dressing is to apply chemical fertilizer after rain or watering after flowering. Dolomite powder or lime can be top applied to soil with a pH value below 6.0.