Possible Clues:

• Cowardly
• Yellow flower survived around banks of Rhone
• On stage in kind of white, red and yellow
• Yellow flower that's capable of shocking with another vibrant colour
• Flower, as it happens, coloured yellow
• I yell drivel (anag) — lacking courage
• Yellow flower existing with cherry
• Weak girl as it happens on burgundy!
• Yellow bloom, as it happens, crimson
• The blooming thing has to be a shade spineless