Native plants have a particularly valuable symbiosis with pollinators. These are species that have co-evolved with pollinators in the same ecosystem. Other plants from the northern hemisphere can play their part being hardy in UK conditions. In many cases they will attract a similar range of pollinators. Not always though; for example there are numerous North American species that have evolved to be pollinated by hummingbirds and we have none.

 Likewise various "exotics" from warmer climbs have a role to play. Some -like Budleja- are so common they don't seem very exotic anymore. The Passion Flower seen above definitely evokes the sense of a hot country but is hardy or at least half hardy in parts of the UK. 

 One tangible benefit of some of these introductions is that they extend the foraging season for pollinators deeper into summer as our native flora starts to fade.