Butterfly bush (also called David's buddleia or Buddleia davidii) is a Class B noxious weed in Washington and its sale has been prohibited since 2016 (with the exception of sterile cultivars); although control is not required in most counties (see the Washington State Noxious Weed Board weed list for details).

Is a buddleia plant a weed?

It became widespread as a weed after the second world war, rushing like wildfire through bombsites and revelling in exposed mortar and rubble. It's now seen growing with abandon in towns and cities across the UK in urban landscapes that mimic buddleia's natural home of rocky mountain tops and dry shingle.

Is butterfly bush butterfly weed?

Although they have similar common names, butterfly bush (Buddleja spp.) and butterfly weed (Asclepias tuberosa) are two different plants. ... Butterfly weed is native throughout the eastern part the U.S., while the more commonly seen butterfly bush (Buddleja davidii) is considered invasive in many areas.