The main reasons for the inability of pear trees to flower are: First, the lack of pollination trees. Most varieties of pear trees are not self-cultivated. If a garden is planted with only one species, or if there is a pollination tree, the flowering period of the main planting species is inconsistent. Second, flowering temperature or frost. During the flowering period, the pollen grains fall on the stigma and do not easily germinate into the style, causing poor fertilization. In addition, insects are inactive at low temperatures, which seriously affects pollination. In the event of late frost, the stigma of the pistil is darkened. Although the flowers can still be opened, they cannot be fruited. It can be improved by cultivating the simultaneous pollinating tree, artificial pollination, or growing the estrogen with the Albit plant. Oxygen Bag,Medical Oxygen Bag,O2 Bag,Oxygen Purse XIAMEN DORRELLA HEALTH TECHNOLOGY CO.,LTD , https://www.dinglimed.com