Black tea (dark tea) is named after the black appearance of the finished tea. It is one of the six major tea groups and is a post-fermented tea. The main production areas are Guangxi, Sichuan, Yunnan, Hubei, Hunan, Shaanxi and Anhui. The traditional black tea is made from high maturity black wool tea, which is the main raw material for pressing tightly pressed tea.
The yellow powder in black tea is commonly known as golden flower, a beneficial microorganism, the so-called golden flower, is in the processing of raw materials through the flowering of this special procedure, specifically in the black tea bricks to cultivate a kind of coronary aspergillus substance called coronary scattered cystic bacteria, commonly known as the golden flower, observed under the microscope, each individual golden flower is umbrella-shaped clusters, the whole body is golden and eye-catching, ringed into a group, evenly distributed.
Yunnan black tea powder ; Hubei black brick tea powderï¼›Pu'er tea power Shaanxi Zhongyi Kangjian Biotechnology Co.,Ltd , https://www.zhongyiherbs.com
The process of making black tea generally includes four steps: killing, kneading, stacking and drying. Black tea is mainly classified as Hunan black tea (Fu tea, Qianliang tea, black brick tea, Tri-tip, etc.), Hubei green brick tea, Sichuan Tibetan tea (border tea), Anhui Gu Yi black tea (An tea), Yunnan black tea (Pu'er tea), Guangxi Liubao tea and Shaanxi black tea (Fu tea) according to geographical distribution.
Subtropical strawberry production technology
**Winter Strawberry Production Management Technology**
**Guangxi Guiping City, Zhejiang High-Quality Strawberry Research and Development Base**
**I. Overview**
Strawberries belong to the genus *Fragaria* in the family Rosaceae. They are perennial herbaceous plants with a short stature, typically reaching about 30 cm in height. As a fruit crop, they produce small berries that are rich in flavor and nutrition.
The fruits of strawberries are bright red, soft, juicy, and have a sweet-sour taste with a pleasant aroma. They are highly popular among consumers worldwide and are considered a delicacy in the fruit industry. According to research, strawberry fruits contain 6–12% sugar, 1–1.5% organic acid, 0.6–1.6% protein, 0.6% fat, 1.4% crude fiber, and 1.7% pectin. In addition, they are rich in calcium, phosphorus, iron, and various amino acids. Notably, the vitamin C content reaches 50–120 mg per 100 grams of fresh fruit, which is about ten times higher than that of apples or grapes. These nutrients are easily absorbed by the body and offer significant health benefits for people of all ages.
Research has shown that a compound called "strawberry amine" may help in treating leukemia and aplastic anemia. More recently, it has also been found to be effective in preventing and managing conditions such as atherosclerosis, coronary heart disease, and cerebral hemorrhage. The vitamins, cellulose, and pectin in strawberries contribute to improving digestion, reducing constipation, and supporting skin health, as well as helping manage hypertension, high cholesterol, and colon cancer. Therefore, the development of strawberry cultivation plays a vital role in enhancing people's quality of life.
Strawberries are one of the earliest fruits to ripen. By late September to early October, planting seedlings can result in harvests from December onwards, filling the gap in the off-season fruit supply. With high yield and economic efficiency, strawberries are considered a valuable crop. In 2008, farmers in the region achieved an average yield of 1,250 kg per mu, with an average selling price of 10 yuan per kilogram, resulting in an income of around 8,000 yuan per mu. This highlights the profitability and potential of strawberry farming.
Beyond fresh consumption, strawberries can be processed into jams, juices, wines, beverages, ice cream, and preserved products. Quick-freezing techniques preserve their color and flavor, making them easier to store and transport. Recently, Chinese strawberry sauce and frozen strawberries have gained popularity in international markets, with large quantities exported annually, especially to Japan, contributing significantly to foreign exchange earnings.
Strawberries were first cultivated in the 14th century, but only wild varieties were grown. In the mid-18th century, large-fruited strawberries spread globally, marking the beginning of modern strawberry cultivation. Today, strawberries are grown in many countries, with global production increasing year by year. According to data from 1988 to 1990, the world produced 2.376 million tons of strawberries, with the U.S. leading at 541,000 tons, followed by Poland, Spain, Japan, and Italy.
**II. Garden Construction and Planting**
**(1) Site Selection and Crop Rotation**
To achieve optimal growth and yield, careful site selection is essential. Strawberries have shallow root systems, with over 70% of roots located within the top 20 cm of soil. Therefore, the soil should be deep, loose, and well-drained, with a pH between 5.5 and 6.5 and at least 2% organic matter. Sandy or clay soils are unsuitable. A high elevation, flat terrain, and good drainage are also important. Large-scale farms may face challenges in soil management and irrigation, so smaller plots (10–20 mu) managed collectively are often more practical.
Strawberries suffer from continuous cropping, where the soil becomes infested with pathogens and the roots release substances that inhibit growth. To prevent this, crop rotation is necessary. A 2–3 year break between strawberry plantings helps restore soil health and reduce disease risks.
**(2) Soil Preparation and Fertilization**
Soil preparation should be done thoroughly before planting. It is best to start one month in advance, especially if there is heavy rainfall. Raised beds (sorghum) are commonly used, with a width of 0.9 m, including a 30–35 cm wide furrow and a 20–25 cm high bed. Two rows of strawberries are planted on each bed, spaced 16–18 cm apart.
Before planting, apply basal fertilizer to enrich the soil. Organic compost or well-decomposed manure is ideal. This ensures sufficient nutrients for the growing season and promotes healthy root development.
**(3) Planting and Spacing**
Strawberries thrive in warm but not excessively hot conditions, with an ideal temperature range of 15–25°C. Autumn is the best time for planting, as the climate allows for strong root development and nutrient accumulation. The optimal planting window varies by region: northern areas in early August to early September, and southern regions in late September to late October.
Planting density depends on soil fertility, seedling quality, and management practices. A density of 7,500–8,500 plants per mu is typical. Proper spacing ensures adequate air circulation and reduces disease risk.
**(4) Improving Survival Rate**
After planting, it is crucial to monitor the seedlings closely. Ensure the planting depth is correct—just covering the crown without burying it. Water regularly, especially in the first few days, to support root establishment. Shade nets can be used to protect young plants from direct sunlight. Removing old leaves before planting also helps reduce water loss and improves survival rates.
**III. Post-Planting Management**
**(1) Fertilization and Growth Promotion**
After planting, apply a balanced fertilizer to promote early growth. Avoid over-fertilizing, as this can burn new roots. Use slow-release fertilizers to ensure steady nutrient supply. Regular monitoring of plant health and soil conditions is key to maintaining productivity.
**(2) Weeding**
Weeds compete for nutrients and water, so regular weeding is necessary. Shallow cultivation is recommended to avoid damaging the shallow root system. Mulch films can also help suppress weed growth.
**(3) Pruning and Leaf Removal**
Remove runners and old leaves to redirect energy toward fruit production. Older leaves lose their photosynthetic ability and may hinder flower bud formation. Keeping 5–6 healthy leaves per plant ensures optimal growth.
**(4) Mulching Techniques**
Mulching with black plastic film helps retain moisture, suppress weeds, and regulate soil temperature. The film should be tightly stretched and secured to prevent wind damage. In some regions, straw mulch is also used to enhance insulation.
**(5) Foliar Fertilization**
Foliar sprays can supplement nutrients and improve fruit quality. Spraying with urea, potassium dihydrogen phosphate, or micronutrients like calcium and manganese can increase yield and fruit size. Apply during the early stages of growth and flowering for best results.
**(6) Watering Practices**
Consistent watering is essential, especially during flowering and fruit development. Maintain soil moisture at around 80% of field capacity. Avoid overwatering, which can lead to diseases like gray mold. Water in the evening after harvesting to minimize evaporation and prevent fruit damage.
**IV. Maturity and Harvesting**
**(A) Ripening Process**
Strawberries take about 30 days to mature under normal conditions, depending on temperature. Higher temperatures shorten the ripening period. The fruit changes color from green to red, becomes firm, and develops its characteristic aroma. Vitamin C and sugar levels increase while acidity decreases.
**(B) Harvesting**
Harvest when the fruit is at least 85% red. Pick in the morning after dew has dried to avoid bruising. Handle fruits gently, cutting the stem with a knife rather than pulling. Harvest in stages, as not all fruits mature at the same time. Store in cool, ventilated containers to maintain quality.
**(C) Packaging**
Proper packaging is essential to preserve freshness and appearance. Use clean, smooth containers such as plastic boxes or enamel pots. Pack strawberries in layers, ensuring they are not crushed. For long-distance transport, use foam boxes filled with ice packs to maintain temperature.
**(D) Transportation**
Transport strawberries carefully to avoid damage. Use padded containers and avoid excessive shaking. Keep fruits cool and dry during transit to prevent spoilage. Efficient logistics ensure that the fruit reaches the market in optimal condition.
**V. Pest and Disease Control**
Pest control in strawberry farming requires the use of professional pesticides. Always follow guidelines provided by agricultural experts. Our base offers technical support and pesticide services. For more information, contact Lao Wu.