The plant won acclaim when introduced at Plantarium in August, picking up a gold medal for Dutch company Valkplant.
It was developed in collaboration with Spring Meadow Nursery in Michigan, USA, which has long been striving to produce a non-invasive Buddleja.
It is protected by Plant Breeders' Rights and Bransford Webbs is the license holder for the UK.
But Gardening Express has sourced the plant from Europe, becoming the first retailer to offer it.
They are offering ‘Blue Chip' as 3-4 litre established plant for £15.95.
Chief executive Chris Bonnett said: "We are hoping this is going to be a trend setter. Early sales in Europe have been good and we are very confident about it."
Exclusive UK breeder Bransford Webbs expect to have about 10,000 plants available in 3 litre pots from next spring.
Managing director Geoff Caesar said the plant could be interesting to both the retail and landscape markets.
‘Blue Chip' grows to about 60cm, does not self seed and was voted the second most popular variety of Buddleja by the public at RHS Wisley.
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