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Monarch® Blue Knight Butterfly Bush

Buddleia 'Blue Knight'

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Monarch Blue Knight Butterfly Bush (Buddleia 'Blue Knight') at Roger's Gardens

Monarch® Blue Knight Butterfly Bush flowers

Monarch® Blue Knight Butterfly Bush flowers

(Photo courtesy of NetPS Plant Finder)

Monarch Blue Knight Butterfly Bush (Buddleia 'Blue Knight') at Roger's Gardens

Monarch® Blue Knight Butterfly Bush in bloom

Monarch® Blue Knight Butterfly Bush in bloom

(Photo courtesy of NetPS Plant Finder)

Height:  4 feet

Spread:  6 feet

Sunlight:  full sun 

Hardiness Zone:  4b

Other Names:  Summer Lilac

Group/Class:  Monarch Collection

Brand:  Walters Gardens

Description:

A compact garden plant with large, showy lavender purple flowers in summer, that mature to deep purple-blue; attracts butterflies; may treat as a perennial and cut it back to the ground each spring as it regrows vigorously and blooms on new wood

Ornamental Features

Monarch® Blue Knight Butterfly Bush features showy panicles of fragrant lavender flowers with purple overtones at the ends of the branches from mid summer to early fall, which emerge from distinctive deep purple flower buds. The flowers are excellent for cutting. It has attractive bluish-green deciduous foliage. The narrow leaves are highly ornamental but do not develop any appreciable fall color.

Landscape Attributes

Monarch® Blue Knight Butterfly Bush is an open multi-stemmed deciduous shrub with an upright spreading habit of growth. Its average texture blends into the landscape, but can be balanced by one or two finer or coarser trees or shrubs for an effective composition.

This is a relatively low maintenance shrub, and is best pruned in late winter once the threat of extreme cold has passed. It is a good choice for attracting bees, butterflies and hummingbirds to your yard, but is not particularly attractive to deer who tend to leave it alone in favor of tastier treats. It has no significant negative characteristics.

Monarch® Blue Knight Butterfly Bush is recommended for the following landscape applications;

  • Mass Planting
  • General Garden Use
  • Container Planting

Planting & Growing

Monarch® Blue Knight Butterfly Bush will grow to be about 4 feet tall at maturity, with a spread of 6 feet. It tends to be a little leggy, with a typical clearance of 1 foot from the ground. It grows at a fast rate, and under ideal conditions can be expected to live for approximately 20 years.

This shrub should only be grown in full sunlight. It is very adaptable to both dry and moist locations, and should do just fine under average home landscape conditions. It is not particular as to soil type or pH, and is able to handle environmental salt. It is highly tolerant of urban pollution and will even thrive in inner city environments. This particular variety is an interspecific hybrid.

Monarch® Blue Knight Butterfly Bush makes a fine choice for the outdoor landscape, but it is also well-suited for use in outdoor pots and containers. With its upright habit of growth, it is best suited for use as a 'thriller' in the 'spiller-thriller-filler' container combination; plant it near the center of the pot, surrounded by smaller plants and those that spill over the edges. It is even sizeable enough that it can be grown alone in a suitable container. Note that when grown in a container, it may not perform exactly as indicated on the tag - this is to be expected. Also note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.

 
 
Hardiness Zone Plant Height Minimum Sunlight
Characteristics
Massing  Garden  Container 
Applications
Flowers  Foliage Color  Attracts Wildlife 
Ornamental Features