I find they look good growing through pale green or variegated foliage Pdb..such as Euonymous "emerald and gold" or "Silver queen " or if you have anything with a similar colour.It also helps to support them,as they do tend to lean,as they get taller..and I just tuck mine into the shrub..The Butterflies love them..

This would also help to disguise the dying leaves which begin to look tatty as the flowers come out. I have grown them once before among pale creamy violas 'Etain', those with the thin lavender edge. I think that worked well, too.

Ive grown mine in a terracotta pot so i can just pop them inbetween shrubs and old daff foliage as needed :)

Many thanks . I think I may also try geraniums. I've got a large clump that I was going to dig up so might be able to put them to some use .