Butterfly bush is one of those shrubs that knows how to put on a show without demanding constant attention. With long flower clusters, sweet fragrance and a steady stream of colorful visitors, it can quickly become a favorite part of the summer landscape. Butterflies, hummingbirds and bees often visit the blooms, making the shrub a lively addition to a sunny garden bed.
Known botanically as Buddleja or Buddleia, butterfly bush is usually easy to grow when planted in the right location. The biggest secret is drainage. This shrub enjoys sunshine, but it does not enjoy sitting in soggy soil with wet feet. Choose a spot with plenty of sunlight and soil that drains well after a heavy rain.
How Much Sun Does Butterfly Bush Need?
Butterfly bush grows and blooms best in full sun. Aim for at least six hours of direct sunlight each day. A location with eight hours of sunlight is even better. When planted in too much shade, the shrub may become lanky, weak and less impressive during flowering season.
Most butterfly bushes are fairly drought tolerant after their roots become established. Newly planted shrubs still need regular watering during their first growing season. Water deeply, then allow the soil to begin drying before watering again. Constantly wet soil can cause root problems and may even kill the plant.
Popular Butterfly Bush Varieties
Butterfly bushes are no longer limited to giant shrubs that take over half the flower bed. Gardeners can now choose from tall varieties, medium-sized shrubs and compact dwarf varieties.
Black Knight Butterfly Bush is a classic variety with deep purple flowers. It can reach approximately 6 to 8 feet tall, making it a good choice for the back of a sunny garden bed.
Miss Ruby Butterfly Bush produces rich pink to reddish-pink blooms. It generally stays closer to 3 to 4 feet tall and wide, making it easier to fit into the average landscape.
Miss Molly Butterfly Bush is another beautiful compact option. Its flowers have an intense reddish-magenta color that stands out among green foliage.
Honeycomb Butterfly Bush offers something different with its soft yellow blooms. It can grow into a larger shrub, so give it enough room to spread out.
For small landscapes, patios or front-yard flower beds, dwarf butterfly bushes are especially useful.
Lo & Behold Blue Chip Butterfly Bush is a compact variety that generally grows around 1 to 2½ feet tall and wide. It works well near walkways or in smaller beds.
Lo & Behold Pink Micro Chip Butterfly Bush is another petite variety with pink blooms. It is a great choice when you want butterfly bush flowers without planting a shrub that tries to become the mayor of the entire flower bed.
Buzz Violet Blue Butterfly Bush is also relatively compact, often reaching around 2 to 3 feet tall. It offers the familiar purple-blue flower color in a smaller package.
When shopping, look for sterile, seedless or nearly seedless varieties whenever possible. Traditional butterfly bushes can reseed heavily in some regions. Check with your local extension office before planting, since recommendations and regulations vary by location.
When Should You Prune Butterfly Bush?
The best time to prune most common butterfly bushes is in late winter or early spring, once the worst freezing weather has passed and new growth begins to appear. Most summer-blooming butterfly bushes flower on new wood, which means the blooms grow on stems produced during the current season.
Pruning encourages fresh growth, keeps the shrub from becoming tall and scraggly, and helps bring the flowers down where people can actually enjoy them. Butterflies may not mind flying eight feet into the air for lunch, but most homeowners would rather see the flowers without climbing a ladder.
For a mature shrub, remove dead or damaged stems and cut the remaining branches back to a manageable height. Depending on the variety and your climate, many gardeners prune the shrub back to approximately 12 to 24 inches above the ground. Compact dwarf varieties usually need a lighter trim.
Avoid heavy pruning in the fall, especially in colder climates. Leaving the stems in place through the winter can provide some protection from cold weather.
One exception is the alternate-leaf butterfly bush, Buddleja alternifolia. This type blooms on older wood and should be lightly pruned after flowering instead of being cut back heavily in early spring. Always check the plant tag before reaching for the pruners.
How to Fertilize Butterfly Bush
Butterfly bush does not need a complicated feeding schedule. In fact, too much fertilizer can create excessive leafy growth with fewer flowers.
A light application of a balanced slow-release fertilizer in spring is usually enough. Apply it after pruning when new growth begins to appear. Follow the product label carefully and avoid piling fertilizer directly against the stems.
Adding a thin layer of compost around the planting area may also improve the soil over time. Keep mulch and compost slightly away from the base of the shrub, especially if your soil tends to stay wet.
How to Propagate Butterfly Bush From Cuttings
Butterfly bush can be propagated from stem cuttings, making it possible to grow additional shrubs from a healthy parent plant. Before propagating a named variety, check the plant label. Some newer cultivars are patented and cannot legally be propagated for resale.
For home propagation of an eligible variety, take softwood cuttings in late spring or early summer. Choose healthy new growth that is flexible but sturdy. Cut a stem approximately 4 to 6 inches long, making the cut just below a leaf node.
Remove the leaves from the lower half of the stem. Dip the cut end into rooting hormone, then place it in a container filled with a moist, well-draining propagation mix. Keep the cutting in bright indirect light and maintain humidity by placing a clear plastic bag loosely over the container. Do not allow the plastic to press against the leaves.
Keep the mix slightly moist but never soggy. Once roots develop and the cutting begins producing healthy new growth, gradually remove the humidity cover and allow the young plant to adjust before transplanting it.
Is Butterfly Bush Good for a Pollinator Garden?
Butterfly bush provides nectar for adult butterflies, bees and hummingbirds, but it should not be the only plant in a pollinator garden. Add native flowering shrubs, perennials and host plants that support caterpillars as well as adult butterflies. A diverse garden provides a longer blooming season and a more complete habitat.
With the right variety, plenty of sunshine and a good spring pruning, butterfly bush can deliver months of colorful blooms. Whether you choose a traditional tall shrub or a tidy dwarf variety, this easy-care plant can add movement, fragrance and summer beauty to your landscape.
