Sometimes when we say romance we mean flowers. Girls like to get flowers and we (men) should study how to give flowers with a special meaning. All flowers have a meaning. The language of flowers is floriography.

The color of flowers could say about your feelings (love or hate).

Now you know what Language of flowers could do and you can give flowers to your girlfriend with special meaning. If she doesn't know this Language of flowers you can explain to her what you want to say by the flowers.

She will like these flowers with meaning more than if you just give her a bouquet and say "This is for you".
Just imagine the situation you come with one big rose (very beautiful red rose) and say "Darling, red color of the flower represents love and my love. I want to say that I love you and even if this flower dies my love will never die." Then you kiss her and… I think that she will not forget this one red flower.
Be romantic