Chinese rose
First, prune the trees according to their age.
Young trees grow vigorously, so we should give priority to shaping, lightly cut and strictly control straight branches. In winter, the upper buds of oblique branches should be stripped to prevent the growth of straight branches. Diseases and insect pests, dead branches, artificially damaged branches and long branches are cut off by thinning. You can choose the upright branches of clustered shrubs to make them grow vigorously and gently remove their hearts to promote their early flowering.
Mature trees should make full use of three-dimensional space to make them blossom more. When pruning in dormant period, the appropriate parts below the autumn shoot should be cut short, and some roots and tillers should be selected year by year, and some old branches should be thinned out to ensure that the branches are constantly updated and keep the complete plant shape.
The old and weak plants are mainly regenerated and rejuvenated, and the nutrition is concentrated on a few axillary buds by the method of heavy and short cutting to germinate strong branches. In addition, weak branches, diseased branches and dead branches should be removed.
Second, trim on time.
Deciduous shrubs can be pruned in winter and summer according to the pruning period. In Beijing area, winter pruning is generally carried out from February, 65438 to the end of February of the following year, and tree species susceptible to freezing injury, such as hibiscus and Lagerstroemia indica, can be appropriately postponed to about mid-March. Summer pruning is carried out after flowering, with the purpose of inhibiting vegetative growth, increasing light, promoting flower bud differentiation and ensuring flowering in the coming year. Pruning in summer should be done sooner rather than later, which is beneficial to control the growth of long branches.
Flowers and trees (in parks and gardens)
Third, according to the habit of pruning
A variety that blooms in spring and has buds on biennial branches. Pruning should be carried out when the leaf buds begin to swell after flowering and have not germinated.
A variety that blooms in summer and autumn and has buds on its branches that year. Flower buds are formed on the sprouting branches of the year, and they should be pruned during dormancy. Because Beijing is cold in winter and dry in spring, pruning should be postponed until the temperature rise in early spring is about to sprout. Leave 2-3 full buds at the base of biennial branches and cut them off again. After cutting, some strong branches can grow. Although there are fewer flowers, because of the concentrated nutrition, there will be bigger flowers.
The flower buds are attached to the perennial branches. The pruning amount of this kind of flowering shrub should be as little as possible, and the dry part of the tip of the branch should be cut off in early spring. In order to prevent too many branches of the same year from affecting the differentiation of flower buds during the growing season, coring can be carried out to make the nutrition more concentrated.
A shrub that germinates and blooms many times a year. It can be pruned many times during the growth period, and cut short when the new shoots are full of buds after flowering. The cut buds can germinate and sprout quickly, forming buds to bloom, and then cut after the flowers wither, and so on.
Ornamental foliage tree species. Cold-tolerant ornamental plants should be pruned in early spring to give full play to the ornamental role of winter branches.