Ageratum houstonianum. The plant (flowers) on this picture is <b>Ageratum houstonianum</b>, most likely cultivar '<b>Blue Horizon'</b> or similiar cultivar for cutting. Picture was taken in the Botanic Gardens of <a href="https://en.wikipedia.org/wiki/Merano" class="extiw" title="w:Merano">Merano</a>. Cultivar (most likely 'Blue Horizon')
<a href="//commons.wikimedia.org/wiki/User:Stephantom" title="User:Stephantom">Stephantom</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>