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Butterfly Bush
Buddleia davidii
Also called summer lilac
Butterfly Bush blooms from June through September.
Mature size, hardiness zones, sun and the trait tags were checked against named botanical sources for this plant. The bloom months and water need on this page were not.
Growing Butterfly Bush
Plant it in full sun. It prefers low water. It is hardy in USDA zones 5–9. Expect it to reach about 6.6 ft tall and 5.9 ft wide at maturity, in roughly 3 years.
When to plant Butterfly Bush
Plant Butterfly Bush in early spring as soon as the soil is workable, or in early fall at least six weeks before your first frost, so roots establish in cool weather. For the middle of its hardy zones 5 to 9 range, spring means March to May and fall means September or October. Once settled, it blooms from June to September.
Month-by-month timing for your zone is on the planting calendar: for the middle of its range, start with zone 7 in March.
Comes in 11 varieties across 6 colors
Same plant, same care - pick the color you are growing.
Good to know about Butterfly Bush
Curated from university extensions, botanic gardens and other primary sources, with the source named on every note.
Worth knowing
Despite the name, it feeds adult butterflies but hosts no native caterpillars: it is Asian-native, so no native caterpillar can develop on its leaves. per NC State and University of Maryland
How much water it needs
Established plants are drought tolerant and want low water in well-drained soil, but a new planting needs regular water, and moderate summer soaks improve bloom in heat. per NC State and Missouri Botanical Garden
Invasiveness varies by region
Aggressively invasive and regulated in the Pacific Northwest and coastal California, but only weedy and less problematic in the hot, humid Southeast. Check your state noxious-weed list. per Cal-IPC and Clemson
Regulated noxious weed
A regulated noxious weed: illegal to sell in Oregon and Washington except approved sterile cultivars. One flower cluster can set more than 40,000 seeds. per Penn State and Cal-IPC
Sterile cultivars are legal
Regulated states allow approved seedless or sterile cultivars, defined as producing less than 2 percent viable seed. These curb the seed spread but still are not larval hosts. per NC State and Cal-IPC
Spider mites and drought
Its main pest is spider mites, which flare when the plant is left drought- and heat-stressed. The fix is not letting a tough plant go bone-dry in heat. per NC State and Clemson
Blooms on new wood
Flowers form on new wood, so cut it back hard, to about 0.3 m (1 ft), in late winter or early spring. Never prune in fall or winter. per NC State and Clemson
What pairs well with Butterfly Bush
Good companions share its growing conditions and add something it lacks: an earlier or later bloom, a lower carpet in front, or structure through winter.
Creeping Phlox
Shares full sun and low water; blooms in mid spring, before this one opens; low at 6 in, to carpet the ground beneath; both are strong pollinator plants, and they feed in different months.
Sea Thrift
Shares full sun and low water; opens in mid spring and overlaps into this one's season; low at 8 in, to carpet the ground beneath; evergreen, so the bed keeps its shape through winter.
Candytuft
Shares full sun and low water; blooms in mid spring, before this one opens; low at 10 in, to carpet the ground beneath; evergreen, so the bed keeps its shape through winter.
Grape Hyacinth
Shares full sun and low water; blooms in early spring, before this one opens; low at 8 in, to carpet the ground beneath; both offer pollinator forage, in different months.
Rosemary
Shares full sun and low water; blooms in early spring, before this one opens; both are strong pollinator plants, and they feed in different months; evergreen, so the bed keeps its shape through winter.
Thyme
Shares full sun and low water; low at 6 in, to carpet the ground beneath; opens in late spring and overlaps into this one's season; both are strong pollinator plants.
Autumn Crocus
Shares full sun and low to moderate water; overlaps, then carries the display into mid fall; low at 6 in, to carpet the ground beneath; both offer pollinator forage.
Flowering Crabapple
Shares full sun and low to moderate water; blooms in mid spring, before this one opens; both are strong pollinator plants, and they feed in different months; taller at 20 ft, for the layer behind it.
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