I'd recommend getting a dream dictionary. For the most part, the interpretations have been tried and true-since ancient Egypt. The majority of dreams are personal messages. You can normally tell when it's something else because you'll feel like you were in a different realm than the ones you normally spend your time in.
Anyways, flowers in a dream (so long as the were fresh and beautiful) predict a good omen of happy adventures. The blade of grass (if it was green) gives one the thought of success in ventures, while the Iris is a symbol of content and prosperity. The nettles are a bit random they too show success through courage to complete a venture.
So basically whatever adventure you will have going will be beautiful and will help you manifest some of your wishes.
I'm Bohemian (blood line, not style) and have not heard about perceptions of someone being given through the gift of flowers in dreams, but I can certainly understand the thought in "real life." One way or the other an Iris is certainly beautiful. It's all about what resonates with you.
Best Wishes