Although the common butterfly bush isn’t native to the United States it deserves a place in your garden. It’s an absolute magnet for butterflies, bees and the occasional hummingbird. Thousands of tiny flowers form along a bottle brush spike and each of the tiny flowers is a tube full of intoxicatingly good nectar. That’s if you’re a butterfly.
Buddleia davidii is the butterfly bush most readily available in garden centers. It’s a rather untidy shrub that can be evergreen, deciduous or herbaceous depending on the climate in which it is grown. Usually it’s somewhat evergreen in our area, although the foliage in winter is just not as attractive as it is during the growing season. The newer varieties hail from China, and can live almost anywhere. It’s not a finicky plant, asking only for reasonable drainage, sun and an infrequent drink of water. Once well established, a good monthly deep watering will usually be enough.
There are many varieties of butterfly bush that are worth considering. Colors range from deep purple to violet, pink, white, red and yellow. The red, Buddleia davidii ‘Royal Red’ is especially attractive to hummingbirds. Because the buddleias attract so many insects, they literally swarm with activity from sun-up to sun down. I’ve seen hummingbirds visit the plants in my yard not just for the nectar, but to feed on some of the smaller insects that also like the nectar.
A gardener from the Norfolk Botanical Garden once told me that the nectar is sweetest during the heat of the day as judged by the heavy mid-day fragrance. I’ve actually observed the most activity in the early evening. But to keep the nectar-filled blooms abundant it’s important that you cut off the spent blooms to keep the side shoots and blooms prolific.
Buddleias are sprawling plants with gracefully arching stems and a loose structure that may not suit some gardens. The good news is that they can be pruned to suit almost any garden design—any configuration that suits the space you have works. Since B. davidii blooms on new wood, I prune mine in late winter, cutting them back to two feet high. I also cut off some of the width since the space I have is rather narrow. But the choice is yours…you can cut them back to the ground, not at all or somewhere in between.
Buddleias are very forgiving and indestructible shrubs, which has advantages and disadvantages. Carefully controlled in an urban setting they can be a delight. But allowing these potentially aggressive plants to naturalize and to spread seeds puts them in the invasive plant category so it’s important to keep a close eye on your plants.