If you want a climber with huge flowers measuring up to 20cm choose clematis 39blue ravine3933 it flowers twice per year first in late spring47early summer then again in late summer when the lavender blue flowers with their contrasting purple47red anthers are slightly smaller this delightful compact climber shows off its blue flowers to best advantage when planted in a partially shaded position the blooms tend to fade in bright sunlight it looks good in containers on trell