Buddleja davidii Black Knight (Butterfly Bush)

Award-winning Buddleja davidii ‘Black Knight’ (Butterfly Bush) is a vigorous large deciduous shrub with gracefully arching branches, studded with lance-shaped, dark green leaves with white-felted undersides, and sweetly scented elongated panicles of dark purple, almost black flowers.

Award-winning Buddleja davidii 'Black Knight' (Butterfly Bush) is a vigorous large deciduous shrub with gracefully arching branches, studded with lance-shaped, dark green leaves with white-felted undersides, and sweetly scented elongated panicles of dark purple, almost black flowers. Borne at the tips of the current year's growth, the long flower spikes, up to 10 in. (25 cm), are on display from mid-summer through early fall and sometimes to the first frost. A superb, easily-grown plant that is favored by butterflies and provides late summer to fall flowers when few other shrubs are in bloom. Excellent for cutting.

  • Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society
  • Grows with an arching, spreading habit, up to 5-8 ft. tall (150-240 cm) and 4-6 ft. wide (120-180 cm). This shrub will naturalize by self-seeding. Where self-seeding is undesired, remove spent flower clusters prior to formation/disbursement of seed.
  • A full sun lover, this plant is best grown in average, medium moisture, well-drained soils. Tolerates a wide range of soil conditions excluding wet conditions. Drought tolerant. This plant will die back in zone 5 but will regrow strongly from the roots.
  • Perfect for shrub borders, foundation plantingsbutterfly gardens, or cottage gardens.
  • Flowers attract butterflies and hummingbirds. Deer and rabbit resistant.
  • Prompt removal of spent flower spikes will usually promote blooms until frost.
  • Propagate by semi-hardwood cuttings
  • Prune in early to mid-spring to allow time for the new growth to mature and flower in the same year. Avoid pruning in winter, as it may lead to frost damage to new shoots.
  • Buddleja davidii species is native to China.
  • Find where this species is invasive in the United States.
  • Discover beautiful U.S. native plant alternatives.

Requirements

Hardiness 5
– 9

Heat Zones 1
– 9

Climate Zones 2, 2A, 2B, 3, 3A, 3B, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, H1
Plant Type Shrubs
Plant Family Buddleja – Butterfly Bush
Exposure Full Sun
Season of Interest Summer (Mid,Late)Fall
Height 5'
– 8'
(150cm
– 240cm)
Spread 4'
– 6'
(120cm
– 180cm)
Spacing 72″ (180cm)
Water Needs Average
Maintenance Low
Soil Type Chalk, Clay, Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Well-Drained
Characteristics Cut Flowers, Fragrant, Plant of Merit, Showy
Tolerance Clay Soil, Deer, Drought, Rabbit
Attracts Butterflies, Hummingbirds
Garden Uses Beds and Borders
Garden Styles Informal and Cottage, Prairie and Meadow