Salvia x jamensis Nachtvlinder
This is one of our favourite of all of the tender salvias, Salvia x jamensis Nachtvlinder, which apparently means night moth. With it's beautifully delicate purple black flowers waving gently in the breeze it is easy to see why. A woody based perennial Nachtvlinder will eventually make 60cm x 45cm or more of colour, but it can be tender in harsher winters. Let the stems stay on over winter and give the plant a good mulch, only cutting back when the harsh frosts have been and gone. It flowers for months - June to November - and is very attractive to bees and other pollinators. An added benefit is supposed to be that when used for underplanting roses it suppresses mildew and blackspot in the roses, but equally it's such a great colour that it will enhance any rose at all! And if that wasn't all already enough to like, the flowers are edible, so you can put some of that colour on your plate too.