There has not been an attempt to answer the first part of the question (the part in italic) therefore here is a link to the question in biology stackexchange: https://biology.stackexchange.com/questions/85104/how-do-we-see-violet-color
If violet is a higher frequency than blue and red why does a combination of red and blue appear as violet color in an RGB image?
Which leads to my second question, where is pink in all this? Does a pink flower emit a combination of violet and red frequencies?