The Buddleia davidii Black Knight Butterfly Bush is a sight for the eyes planted in any butterfly garden landscape! As long as you have a sunny planting spot this flowering perennial shrub will flourish with big purple flower heads whose fragrance will attract butterflies and other pollinators like bees or hummingbirds to your landscape. This flowering butterfly bush plant features very dark purple conical flower heads that have a bloom time from early to mid-summer to early fall at their prime. You can start seeing the clusters of flowers as early as May or June and they will last all the way until September. They will appear on a long shrub-like spike that surrounds the circumference of the plant.