Not for long - Sambucus gets huge and needs a lot of root room - try the Lavender in the middle with Ophiopogon nigrescens (black grass) round the outside instead. Has the advantage of being evergreen, so black leaves present all year to contrast with the lavender, and it produces lovely little pale pink flowers too.

I like the sound of that Bamboo, black grass has always been a favourite of mine and I've got several small pots of lavender (another favourite) that I need to do something with!