My sister-in-law's wedding shower was last weekend. The weekend before that, I received a bag of these lovely paper flowers (they are here, if you're interested). The colors of the flowers just happened to coordinate with the colors in the vintage wedding wrapping paper I found, so I had to use them for her card.
Clusters of brightly colored flowers can only be wildflowers, so that idea is what prompted the saying. I know I've heard something similar before, but Google couldn't help me identify it, so I just winged it. It worked. I think the saying is very appropriate for young, vibrant, almost-newlywed love. :)