[From Clematis For Everyone
, pp. 10-11:] Purple
are the predominant colours, although regrettably the blue is not a clear blue as with a delphinium [another member] of the Ranunculaceae family... The reds
also are not a pure colour since the nearest true red contains shades of blue or purple... The pinks
are of various pastel shades, frequently having two tones, giving a bar or star like appearance... Even the deepest shades of pink fade gently in bright sunlight... A large-flowered, deep buttercup yellow
clematis is yet to be produced... the yellows are represented by the deep yellow, nodding flowers of C. tangutica
-flowered clematis are very elegant... when plants are late in producing their flowers due to bad weather conditions, some clematis flowers often open green
, the correct colour appearing later as the flowers age and the tepals are subjected to the sun's rays... [often] the flowers do not completely attain the true colour... [occurs most often] with white, or very pale pink or pale blue cultivars...