On that very subject, only ever give or receive plants when you are 100% certain of their identity. The invasion of harmful, non native plants such as Japanese Knotweed and Rhododendren could well have started from the best of intentions.
Get it right, though, and imagine these splendid Great Mullein Verbascum thapsus (below), for example, growing in each garden in your road… what a fantastic corridor or chain this would be for the bees, butterfies and other insects.
Similarly, when planting more than one of any native wildflower plant, always group them together. Insects then have ready access to an easy feast!
In the wild, it’s ‘survival of the fittest’. Native wildflower plants are used to snuggling up nice and close, being overcrowded and fighting for the elements they need. Again, several of the same wildflower are happiest planted near to each other rather than in splendid isolation.