Plant Type: Perennials
A classic Buddleia. This variety has long been treasured for its showy panicles of very dark violet to dark purple flowers which appear over a long period from late summer into fall. The long, gray-green leaves and tall, upright stems form a large shrub which can grow up to 10' tall. 'Black Knight' has proven to be a vigorous grower and a very hardy selection.
Butterfly Bushes have certainly earned their place in the garden over the years, and its easy to see why. Just when we need a breath of fresh air in the late summer heat, they happily burst into bloom. At a time when many other plants are already spent, Buddleias are just beginning their show. Their passive coloring and texture makes a wonderful backdrop for perennials, and you'll love the butterflies, bees, and hummingbirds that flock to their honey-scented blossoms.
Growing & Maintenance Tips:
Buddleias should be planted in a full sun location with fertile, moist, well-drained soil. Studies have shown that adding lime to the soil will result in increased growth and better floral quality. They are also moderately drought tolerant once established. Since they frequently die all the way back to the ground in northern winters, it is best to cut back all of the old wood to about 12" in the spring. Doing so will result in more compact plants. They will quickly grow back to their normal height by fall and will flower just as prolifically in late summer since they bloom on new wood. You may notice that the flowers tend to be longer and deeper colored in cooler weather. Buddleias tend to break dormancy late in the spring, so don't worry if you don't see anything happening with them when your other shrubs start to leaf-out. These are very durable and reliable plants.
Flower ColorViolet to dark purple
Foliage ColorGray green
Plant Spread5-10 ft.
Aster-New York (Aster dumosus), Black-Eyed Susan (Rudbeckia fulgida), Blanket Flower (Gaillardia ), Blue Mist Shrub (Caryopteris divaricata), Clematis (Clematis ), Coneflower-Purple (Echinacea purpurea), Daylily (Hemerocallis ), Grass-Ornamental (Pennisetum orientale), Grass-Ornamental (Miscanthus sinensis), Obedient Plant (Physostegia virginiana), Phlox-Tall Garden (Phlox paniculata), Russian Sage (Perovskia atriplicifolia), Snakeroot-Chocolate (Eupatorium rugosum), Stonecrop-Showy (Sedum spectabile), Willow Leaf Sunflower Hybrid (Helianthus salicifolius)
Plant Height8-10 ft.
Soil MoistureLow to average water needs
Characteristics & Attributes
Fragrant, Border, Specimen, Drought tolerant
Bloom TimeLate summer to fall
Critter ResistanceDeer resistant