紫薇为千屈菜科落叶小乔木或灌木,又名百日红、无皮树、怕痒树。其圆锥花序顶生在当年生枝上,花色粉红、紫红、淡血青、白色,花冠多皱折,花期正值盛夏,长达百日,因此是园林花木中重要的夏季观花树种。紫薇耐修剪,发枝力强,新梢年生长量很大,一年生枝可长达1～2米。它开花的次序是下枝先开花,依次向上进展,一般在7月上旬始花。9月下旬进入末花期。经试验,如在夏季对紫薇花枝进行修剪,可使其单株延长花期10天左右。方法是,按开花先后依次打掉 Crape myriadaceae families deciduous trees or shrubs, also known as 100 days red, no skin tree, itch tree. The top of its panicles in the current year branches, color pink, purple, pale blood blue, white, corolla and more creases, flowering period summer, up to 100 days, it is an important ornamental tree species in the garden flowers. Ziwei resistant to pruning, twig strong, shoot a large annual growth, annual branches can be as long as 1 to 2 meters. The order of its flowering is under the first flowering branches, followed by upward progress, usually in early July before flowering. In late September into the late flowering. After testing, such as the summer crape myrtle branch pruning, can extend the flowering period of about 10 days. The method is, according to flowering successively destroyed