Flowering shrubs make quite an impression when they burst into bloom in the spring or summer. In addition to adding impressive color to the garden, they often are fragrant and attract pollinators. Like other shrubs, flowering shrubs provide structure in the garden. They can be grouped together to create a hedge or planted as an accent plant. Some popular flowering shrubs include lilacs, magnolias, rhododendron, butterfly bushes and roses. When buying flowering shrubs for sale, take into account the shrub's hardiness zone and sunlight requirements (full sun, partial shade or full shade). Other factors to consider are its mature height and spread, maintenance and pruning requirements, flower and foliage color, and bloom time.