Plastic pruning in winter has an important influence on the growth and tree shape of paulownia. If it is not pruned in time and reasonably in winter, the tree shape will be chaotic, the main branches will be long, and the leaves will be few or low, which will greatly reduce its ornamental value and shading effect. Timely and reasonable pruning can make the tree magnificent, straight and beautiful in a short time, with dense branches, many symmetrical side branches and lush leaves, which enhances the natural immunity of the tree. The winter pruning of paulownia trees can be carried out before the leaves of paulownia trees fall off in autumn and winter, the soil freezes, and the tree sleeps until the sap flows out in the next spring. For newly planted young trees, when the stem is as high as 2.7 ~ 3 meters, it is called "fixed stem". Pruning can be based on the overall view of the whole tree and the decision of future cultivation direction. First, cut the upright branches and drooping branches, then cut the branches of diseases and pests, cross branches, weak branches, inward branches and branches that affect traffic facilities, and finally leave 3 ~ 4 strong main branches. The main branches should be conducive to plastic surgery in the future, grow strong and have moderate angles. After selecting the main branch, cut it short at 30 ~ 40 cm near the base, the section should be smooth without damaging the bark, and the section should be coated with protective agent to avoid pests and diseases and water transpiration. Smoothing wounds can also promote callus formation, which is beneficial to wound healing and prevent bacterial infection. The wound protective agent can be waxed, coated with Jining hair tonic, tung oil or paint. Young trees grow every 3-4 years and are pruned in winter. Generally, three or four main branches can be kept basically unchanged for the first time, and then 1 ~ 2 robust branchlets can be kept on each main branch, and the length can reach 20 ~ 30cm when cut short. The lateral branches on the branchlets can be retained according to the specific situation. For example, under the condition that the communication line near the tree is not high, only 3-4 short main branches left after the first drying can be kept, which can reduce the height of the whole tree and increase the transparency of the branches and leaves, and will not affect its growth, but also can well keep the paulownia tree.