Blue Chip

Butterfly Bush

Variety Description

Varieties used for comparison: 'Adokeep' (Adonis Blue) and 'White Ball'

Summary: 'Blue Chip' has denser branching and foliage than 'Adokeep'. 'Blue Chip' has a taller plant height than 'Adokeep'. 'Blue Chip' has a longer and wider leaf than the reference varieties. 'Blue Chip' has an ovate leaf shape while the reference varieties have an elliptic to lanceolate leaf shape. 'Blue Chip' has less pubescence on the upper side of the leaf blade than the reference varieties. 'Blue Chip' has a smaller corolla diameter than 'Adokeep'. 'Blue Chip' differs from the reference varieties in the colour of the corolla and flower bud.

Description:

SHRUB: deciduous, bushy growth habit, medium to many branches, medium to dense foliage
STEM: thick, medium anthocyanin colouration, edged, light green and grey brown, no twisting

LEAF: opposite arrangement, simple, ovate, acuminate apex, acute base, crenate to dentate margin, weak glossiness on upper side, absent to very sparse pubescence on upper side, dense tomentose pubescence on lower side, very weak leaf fragrance, medium green on upper side, grey green on lower side, no variegation, petiole present

FLOWER: panicle, salverform shape, both terminal and axillary in position, semi-erect attitude, weak fragrance
FLOWER BUD: rounded apex, violet
COROLLA: concave in profile, 4 to 5 lobes, rounded lobe shape, medium undulation of margin, obtuse apex with crenate to serrate margin, violet on upper side with blue violet margin
COROLLA TUBE: yellow orange on inner side, brown reddish purple on outer side

Origin & Breeding History: 'Blue Chip' originated as a third generation descendant from a cross between 'Honeycomb' and ('Nanho Purple' x Buddleja lindleyana), made in 2001 at North Carolina State University in Raleigh, North Carolina, USA. The seeds resulting from the cross were harvested in fall of 2001 and germinated in a greenhouse at North Carolina State University in the winter of 2002. The resulting seedlings were planted in field trials in spring of 2002. These plants flowered in summer of 2002 and seed was collected off of all plants and bulked. This bulk seed was germinated in the winter of 2003 and the resulting seedlings were planted in the field in spring of 2003. These plants flowered in summer of 2003 and one plant, designated NC2003-7, was selected for its compact growth habit and flower colour. Open pollinated seed was collected off this selection and the bulk seed was germinated in the winter of 2004. The resulting seedlings were planted in the field in the spring of 2004. These plants flowered in the summer of 2004 and a single plant, designated NC2004-9, was selected for its multi-branched, compact growth habit and attractive flower colour. This single plant was given the denomination 'Blue Chip'. The first asexual propagation by softwood to semi-hardwood stem cuttings was conducted in the fall of 2004, in Raleigh, North Carolina, USA.

Tests & Trials: 'Blue Chip' was tested in an outdoor trial during the spring/summer of 2008 in St. Thomas, Ontario. The trial consisted of a total of 16 plants of the candidate variety and 8 plants of the reference varieties. All plants were grown from 4 1/2 inch rooted liners in the spring of 2007 and transplanted into 3 gallon containers. Observations and measurements were taken from 10 plants of each variety on July 25, 2008. All colour measurements were made using the 2001 Royal Horticultural Society (RHS) Colour Chart.

Comparison tables for 'Blue Chip' with reference varieties 'Adokeep' and 'White Ball'

Plant height (cm)

Leaf length (cm)

Leaf width (cm)

Corolla diameter (mm)

Flower colour (RHS)

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Butterfly Bush: 'Blue Chip' (left) with reference variety 'White Ball' (right)

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Butterfly Bush: 'Blue Chip' (left) with reference variety 'Adokeep' (right)

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Butterfly Bush: 'Blue Chip' (left) with reference varieties 'Adokeep' (centre) and 'White Ball' (right)