We have found 15 plants that meet your criteria.

clematis (group 2)
Clematis florida var. sieboldiana clematis (group 2) Unusual flowers £15.99 Buy
clematis (group 2)
Clematis Crystal Fountain ('Evipo038') (PBR) clematis (group 2) Unusual lavender flowers £12.99 Buy
clematis (group 3)
Clematis 'Étoile Violette' clematis (group 3) Produces masses of deep purple blooms £12.99 Buy
clematis (group 3)
Clematis Happy Birthday ('Zohapbi') (PBR) clematis (group 3) Dark flowers become paler as they age £14.99 Buy
clematis (group 1)
Clematis 'Purple Spider' clematis (group 1) Often has a second flush of flowers £12.99 Buy
clematis (group 3)
Clematis 'Purpurea Plena Elegans' clematis (group 3) Small, double dusky-purple flowers £11.99 Buy
clematis (group 3)
Clematis 'Romantika' clematis (group 3) Stunning, almost black blooms £12.99 Buy
New
clematis
Clematis 'Shikoo' clematis Lush double flowers £5.99 Buy
clematis (group 3)
Clematis 'Warszawska Nike' clematis (group 3) Sumptuous deep purple flowers, £9.99 Buy
clematis (group 3)
Clematis 'Black Prince' clematis (group 3) Beautiful deep purple flowers £12.99 Buy
New
clematis (group 2)
Clematis 'Shikoo' clematis (group 2) Lush double flowers £12.99 Buy
clematis (group 3)
Clematis × aromatica clematis (group 3) Rich purple star-shaped blooms £12.99 coming soon
clematis (group 3)
Clematis × triternata 'Rubromarginata' clematis (group 3) Delicious, marzipan-scented flowers £11.99 coming soon
clematis (group 3)
Clematis 'Sweet Summer Love' clematis (group 3) New for 2012 £14.99 coming soon
clematis (group 3)
Clematis 'Walenburg' clematis (group 3) Rediscovered in the gardens of a castle in Holland £12.99 coming soon