I am really happy with the echium vulgare / Viper's Bugloss. We've had a couple of good frosts and it's unfazed, flowering away at a time whem not a lot else is and the bees are liking that. It's tough, drought tolerant, can be invasive, but that can also be controlled from the beginning by not letting it 'go wild', cutting the seedheads before they scatter. I'm thinking that it will be my repeat performer in the front border, weaving through the grasses and shrubs. In the lower left hand corner of the first pic, there's a bee on it....
Just look at this digiplexis! It not only has never stopped flowering, here it is in the midst of November and frosts and it's still putting out new buds...Super Plant!