Hedge Woundwort (Stachys sylvatica) is quite a common "wayside weed" but rarely thought of as a garden plant though I like having a patch of it.
 Where there's Woundwort there's bees. The smaller and medium sized bumblebees are all over it. The markings on the flowers in close up make it clear that a flower is what it is to attract pollinators and guide them in to do their work.