10 Best and/or easiest for the garden grouped per flower colour

The list below is a choice of the cultivars which are the easiest for the garden. This list is a direct source of discussion as this does not mean that cultivars not in the list should not be grown. Contrary. But Clematis likes, especially the plants with thick fleshy roots, enough watering and feeing in the growing season. When this care is not given a choice from the list might be a good start. 

dark violet-blue
Clematis BLUE PIROUETTE
Clematis 'Etoile Violette'
Clematis 'Fascination'
Clematis HAPPY BIRTHDAY
Clematis 'Jackmanii'
Clematis JACKMANII PURPUREA
Clematis 'Star of India' 
Clematis SUPER NIGHT
Clematis SUPER NOVA
Clematis 'The President'

yellow
Clematis 'Bill MacKenzie'
Clematis 'Helios'
Clematis 'Last Dance'
Clematis rehderiana
Clematis serratifolia

pale violet-blue
Clematis 'Arabella'
Clematis 'Betty Corning'
Clematis 'Blue Boy'
Clematis BLUE RIVER
Clematis 'Dutch Sky'
Clematis 'Emilia Plater'
Clematis 'Little Bas'
Clematis 'Prince Charles'
Clematis SEA BREEZE
Clematis 'Semu'

red
Clematis 'Gravetye Beauty'
Clematis 'Madame Julia Correvon'
Clematis 'Princess Diana' 
Clematis 'Purpurea Plena Elegans' 
Clematis QUEEN MOTHER 'Zoqum'  
Clematis 'Royal Velours'
Clematis ROSALYN
Clematis STAR OF PAKISTAN
Clematis 'Ville de Lyon'
Clematis 'Walenburg'

pink
Clematis 'Comtesse de Bouchaud' 
Clematis 'Dr Ruppel' 
Clematis 'Hagley Hybrid'  
Clematis 'Hendryetta'
Clematis I AM HAPPY
Clematis I AM LADY Q
Clematis INSPIRATION
Clematis 'Mayleen' 
Clematis SUPER CUTE
Clematis WONDERFUL

white
Clematis 'Anita' 
Clematis FOREVER FRIENDS
Clematis 'Guernsey Cream'
Clematis 'Huldine'
Clematis 'Kaiu'
Clematis mandschurica
Clematis 'Maria Cornelia'
Clematis SPRING JOY
Clematis terniflora
Clematis WHITE ARABELLA

2 colours
Clematis PRINCESS KATE