We have found 111 plants that meet your criteria.

Purple Sage ‘Salvia officinalis Purpurascens’ Attractive red-purple young leaves £4.99 Buy
Russian Sage ‘Perovskia abrotanoides’ Silvery white aromatic foliage with long lasting blue flowers £7.99 Buy
Price Pruned
Russian Sage ‘Perovskia atriplicifolia Little Spire’ A shorter form of the popular Russian sage NOW £7.99 Buy
Russian Sage ‘Perovskia Blue Spire’ Violet-blue flowers and silvery foliage. Great planted en masse £7.99 Buy
Sage ‘Salvia patens’ Large, stunning blue blooms £5.99 Buy
Salvia May Night ‘Salvia x sylvestris Mainacht’ Large indigo-blue flowers £5.99 Buy
Sea Holly ‘Eryngium bourgatii’ Lovely silver-veined foliage £5.99 Buy
Sea Holly ‘Eryngium bourgatii Picos Amethyst’ New variety with deep blue flowers £7.99 Buy
Sea Holly ‘Eryngium x zabelii Jos Eijking’ Spiny metallic-blue flowers in late summer £7.99 Buy
Sea Holly (Eryngium planum Blue... ‘Eryngium planum Blauer Zwerg’ Dwarf variety with deep blue flowers £5.49 Buy
Price Pruned
Siberian Bugloss ‘Brunnera macrophylla Jack Frost’ large, silvery leaves and frothy blue flowers NOW £7.99 Buy
Price Pruned
Siberian Bugloss (syn. B. macrophylla... ‘Brunnera macrophylla Dawson's White’ An excellent groundcover NOW £8.99 Buy
Siberian Flag ‘Iris sibirica Perry's Blue’ Looks great planted in bold clumps £5.99 Buy
Siberian Flag ‘Iris sibirica Silver Edge’ Blue flowers edged with white £5.99 Buy
Siberian Flag ‘Iris sibirica Tropic Night’ Violet flowers with yellow throats. Good for boggy ground £5.99 Buy
Siberian Iris ‘Iris sibirica Caesar's Brother’ Intense violet flowers. Great in boggy ground £5.99 Buy
Siberian Iris ‘Iris sibirica Flight of the Butterflies’ Pretty violet-blue flowers £5.99 Buy
Spanish Sage ‘Salvia lavandulifolia’ A great alternative to common sage £4.99 Buy
Speedwell ‘Veronica austriaca subsp. teucrium Royal Blue’ Slender spires of sky blue flowers £5.99 Buy
Speedwell ‘Veronica austriaca teucrium Crater Lake Blue’ Ultra-marine flowers £5.99 Buy