Perovskia 'Filigran' (Russian Sage):
Silvery foliage & spikes of purple flowers in mid-summer. More upright than other cultivars. Lovely winter stem effect. Hardy. Up to 1.5m.
Persicaria microcephala Red Dragon' (PBR):
Stunning foliage with upright stems of lance-shaped purple-green leaves, with delicate chevron markings in white. Best leaf colour in full sun. Hardy. Up to 90cm.