We have found 13 plants that meet your criteria.

Price Pruned
Lavandula angustifolia 'Munstead' Lavender A compact variety with blue-purple flowers NOW £4.99 Buy
Price Pruned
Rosa Rhapsody in Blue '('Frantasia') (PBR)' rose (shrub) The closest to a blue rose NOW £10.99 Buy
Price Pruned
Buddleja 'Lochinch' Butterfly Bush Fragrant violet-blue flowers all summer NOW £5.99 Buy
Caryopteris x clandonensis 'Heavenly Blue' Bluebeard Piercing, dark blue flowers £6.49 Buy
Ceratostigma willmottianum 'Forest Blue' Hardy Plumbago Foliage turns wonderful autumnal colours £6.99 Buy
Hydrangea aspera 'Villosa Group' Rough-leaved Hydrangea Long-lasting, deep mauve flowers in autumn £10.99 Buy
Hydrangea macrophylla 'Mariesii Perfecta' Lacecap Hydrangea (syn. Blue Wave)... Pink or pale blue lacecap flowers £6.99 Buy
Hydrangea serrata 'Bluebird' Hydrangea Distinctive blue flowers and autumn colour £8.99 Buy
Price Pruned
Perovskia atriplicifolia 'Little Spire' Russian Sage A shorter form of the popular Russian sage NOW £7.99 Buy
Price Pruned
Rhododendron 'Blue Diamond Group' Dwarf Rhododendron Vivid violet flowers NOW £10.99 Buy
Rosmarinus officinalis 'Miss Jessopp's Upright' Rosemary Lavender-blue flowers £5.99 Buy
Price Pruned
Vinca major Greater Periwinkle Elegant blue-violet flowers NOW £4.99 Buy
Vinca minor Lesser Periwinkle Superb ground cover £5.99 Buy