Buddleia Bush - Buddleia Bush White has wonderfully fragrant flowers on arching stems that attract a profusion of butterflies and hummingbirds to gardens. Blooms on new wood. Butterfly bush thrives in temperatures 75 degrees Fahrenheit or above, and if your summer has been unseasonably cool, the plants may withhold flowers for that year. Butterflies swarm to their blooms all summer long. Flowers in elongated clusters on arching branches to 10 feet tall if not cut back, and half that size if cut back. The blooms come from early summer to first frost. The foliage is willow-like and grayish green.