Different varieties of grapes and grape growing areas with different climatic conditions need to use different grape fruit bags. However, some of our fruit farmers are very blind when choosing fruit bags for grapes. Sometimes they face different fruit bags with different thicknesses, sizes, colors, light transmittance and shading rate, fruit bags with air holes and fruit bags without air holes. Colorful fruit bags make fruit farmers not know which is the most correct choice, and sometimes even some fruit farmers will buy the cheapest fruit bags. Such as plastic fruit bags, wood pulp paper fruit bags, white fruit bags, green fruit bags, light-colored fruit bags, high permeability fruit bags, shading fruit bags, insect-resistant and disease-resistant fruit bags, etc.

As far as the size of grape fruit bag is concerned, you can choose the most suitable grape fruit bag according to the ear size (ear width, ear length and ear shape) of your own grape variety. Commonly used grape fruit bags mainly have several common sizes, such as 38 cm *28 cm, 20.3 cm *29 cm, 19 cm *26.5 cm,17.5cm * 24.5cm.. Too large or too small fruit bags will affect the normal growth and development of grape ears. Generally speaking, the size of the selected fruit bag is slightly larger than the mature grape ear, which is the most suitable.

As far as the weight of grape fruit bags is concerned, different weight fruit bags directly determine the air permeability and light transmittance of fruit bags, so when choosing fruit bags, we should also pay attention to the single weight of fruit bags (generally in grams). Take the common 38-gram fruit bags, 36-gram fruit bags, 34-gram fruit bags and 32-gram fruit bags as examples: high-altitude vineyards, late-maturing grape varieties and rainy and windy grape growing areas are more suitable for choosing fruit bags above 38 grams; For low-lying vineyards, early-maturing grape varieties and grape growing areas planted under rain-proof conditions, fruit bags below 32 grams are more suitable; For vineyards with flat terrain or northern plains, grape growing areas with relatively little precipitation and medium-ripe grape varieties, 34-36 grams of fruit bags can be selected according to the situation.

As far as the material of grape fruit bag is concerned, paper bag can be used for most grapes because of its good air permeability, good light transmittance, good antibacterial property and good weather resistance. But for those vineyards planted in the open air, with much rain and high humidity, it is usually best to choose plastic film bags with strong weather resistance.

From the perspective of permeability and light transmittance of grape fruit bags, grape varieties (such as green grape varieties or most Kyoho grape varieties on the surface after maturity) planted in the open air, with strong light during fruit expansion, shed planting and without strong light during coloring can choose fruit bags with good shading rate (such as green fruit bags of green fruit varieties and white vinyl bags of Kyoho varieties). White, light-colored and transparent fruit bags can be selected for grape varieties that need a lot of light and are not easy to color (such as grapes with red, purple and black ripe surfaces) and Eurasian grapes with sufficient light; For grape varieties (such as Meirenzhi and other grape varieties) with thin skin, difficult coloring and easy sunburn, fruit bags with good light transmittance, low shading rate and sunburn resistance should be selected; For grape varieties (such as most red grapes) that need better coloring and lower fruit acid and sweetness, plastic film belts, glass paper bags and other fruit bags can be selected to ensure light transmission and coloring. Colleagues reduced the temperature in the fruit bag to promote the reduction and sweetening of fruit acid.

In a word, thin bags are suitable for early-maturing vineyards with less rain, thick bags are suitable for late-maturing vineyards with more rain, wood pulp paper bags with good antibacterial, waterproof and breathable properties are suitable for open-air vineyards, high-breathable fruit bags and non-woven fabric +bb film double-sided fruit bags are suitable for greenhouse grapes, while red/black/purple grape varieties require higher light transmittance for fruit bags, and green grape varieties need more shading.

When bagging grapes, it is usually suggested to start bagging immediately after fruit setting is stable, heading and fruit thinning are completed. Because if the bagging time is too late, grapes are easily infected with pests and diseases. In addition, bagging should be completed before the rainy season, and high temperature weather after rain should be avoided, otherwise it will cause serious sunburn. However, the bagging time should not be too early. If it is too early, the fruit will become smaller.