Butterfly bush (Buddleia davidii), the cold-tolerant variety, grows in U.S. Department of Agriculture plant hardiness zones 5 and above. Wooly butterfly bush (Buddleia marrubiifolia) grows in USDA zones 8 through 10b. Wooly butterfly bush is a better choice in hot climates because it tolerates heat well.

Butterfly bushes are popular and hardy from Zone 5 south to Zone 9. In the colder zones, they die to the ground each year like a perennial plants, but in more southern regions, they are somewhat evergreen. In the warmer states, butterfly bushes often grow to 10 or 12 ft.

Buddleia davidii and Buddleia alternifolia (which is more of a weeping variety) are both fast-growing shrubs that will grow to around 3 metres (10ft) tall. They are drought tolerant and will grow in most soil types as long as its well-drained. ... Buddleia is deciduous but often hold their leaves in the winter.. . . . .364011236342!]0000000000000009783314146049!]