Production and processing Technology of greenhouse Tea in North China

As a successful example of "moving south to the north", Rizhao green tea accounts for more than 50% of the total area of tea gardens in Shandong Province. It has the unique quality of "delicious taste, strong aroma and resistance to brewing" and enjoys a good reputation at home and abroad. In recent years, with the adjustment of agricultural structure, as an important part of facility agriculture, greenhouse tea production has formed a certain scale and become a pillar industry for agricultural development in tea areas and an important way to increase farmers' income. The production and processing technology of winter tea in greenhouse is introduced as follows:

1 selecting land to build a shed

1.1 Rizhao is located at 35-38 °N, which is the northern limit of tea tree growth. Tea trees can be planted in the area south of this latitude. The principle of site selection: first, the gentle slope from the leeward to the sun. Second, the soil layer should be thick to facilitate the tea tree to take root. Third, the pH value of soil is between 4 and 6.5.

1.2 the construction of the greenhouse is generally made of steel frame non-column single slope semi-arch greenhouse, with a length of 60mm 100m, a span of 7m 9m and a ridge height of 2.4.02.8m. The greenhouse film should be non-dripping film with high light transmittance, and the greenhouse surface should be covered with 5cm thick thermal insulation grass curtain.

2 main points of cultivation

2.1After deep turning and fertilizing, the soil in the shed should be deeply ploughed and fertilized, and the ploughing depth should be above 80cm, and then trench should be opened according to the planting baseline, and the width and depth of the ditch should be 40cm respectively. After opening the ditch, the soil fertilizer 5000kg and phosphate fertilizer 50kg should be applied per mu on average, and then the soil fertilizer should be mixed well and filled flat.

2.2 moderate close planting should choose varieties with strong cold resistance, such as Longjing 43, Bai Maozao and Xinyang 10, which are suitable for making famous tea. In order to see the benefit as soon as possible, the older tea trees outside the shed can be directly selected for transplanting. Single-row and double-row close planting, single-row planting row spacing 80~100cm, hole spacing 33cm, double-row planting large row spacing 80~100cm, small row spacing 35~40cm, hole spacing also 33cm.

3 greenhouse management

3.1 Fertilizer and water management fertilization should be based on "foot base", "more pursuit" and "frequent spraying". "foot base" refers to applying sufficient base fertilizer before and after White Dew in autumn, opening deep and wide 25cm ditches in the center of the planting line, applying soil miscellaneous fertilizer 3000kg or cake fertilizer plus phosphate fertilizer 30kg per mu. "multiple topdressing" means that topdressing should be carried out after each harvest, and it should be trenched under the crown according to the standard dosage of 100kg dry tea supplemented with pure nitrogen 12kg and pure phosphorus pure potassium. "constant spraying" means that foliar fertilizer is often sprayed during the growth of tea trees, and the canopy is evenly sprayed with 0.5% urea solution or tea trees with diluted concentration of 180 to 200 times in the morning.

Tea plant is a leaf crop, and its photosynthesis has a great demand for water. Ensuring water supply is an important measure to obtain high yield. Watering tea in greenhouse should follow the principle of "less spraying and frequent irrigation", replenish water at any time, and micro-irrigation technology is better.

3.2 temperature management during the day, the greenhouse temperature is 22: 28 ℃, when it is over 30 ℃, it should be ventilated and cooled, at night, it should be kept at 10: 15 ℃, and when it is below 5 ℃, it should be protected by heating. In addition, tea trees prefer a shady and humid environment, and the air relative humidity should be kept at 70%-80%. Shading measures should be taken in case of high temperature and strong light.

3.3 pest control of tea garden pests are mostly hibernating in winter, so it is not a threat to the structure of winter tea in greenhouse, so there is no need to apply pesticides. For some diseases such as red leaf spot of tea, carbendazim and carbendazim can be sprayed to prevent and protect them during the period of stopping mining. It is absolutely forbidden to use highly toxic, highly toxic and high residual pesticides in tea gardens to ensure the production of pollution-free tea that meets the standards.

(4) harvesting and frying

Greenhouse tea is of high quality, good market and high price, and most of it is made into high-grade famous tea. Harvesting should be timely, appropriate methods, strict standards, and appropriate retention. On this basis, highlight the word "early", when 5% of the new shoots on the surface meet the picking standard (1 leaf and 1 bud), pick immediately.

Tea can be made into different shapes according to market demand, and Rizhao area is often made into curved strip, flat and needle-shaped tea. Each shape has its own unique production process, but it is roughly divided into four parts: first, spread out to dry. Spread it on the bamboo mat or cement floor for 2-4 hours, the thickness is 3~5cm, and the water content of fresh leaves can be reduced to about 70%. The second is to kill the youth. In order to improve the quality of killing green, to kill evenly and thoroughly, we must follow the principle of "high temperature killing, first high and then low, combination of shaking and boredom, more shaking and less boredom, old leaves killing, old leaves killing". The third is styling. Including manual modeling and machine modeling. Fourth, it is dry. Reduce the moisture in the tea to about 5%. The commonly used tea-making machines include 6CSM-30 famous tea anti-green machine, 6CRM-25 famous tea kneading and twisting machine, 6CH-3 automatic famous tea dryer and 6CD-42 famous tea multi-function machine, which are all the preferred models for the development of tea mechanization technology, which are worth popularizing.