I got this from the University of Washington Panhellenic website (Seattle, Washington) and I just thought it was a lovely idea....
A parent came up to me with a great recommendation to put on this web page. She stated, being a parent of two girls that have gone through formal recruitment week and having another go through this year she felt that parents should be aware that flowers is a great surprise after your daughter has moved into her house. Being in a house myself a handful of girls received flowers sent after Bid Day and since I was not one of them I know how it feels. It's an emotional time leaving home for possibly the first time so receiving flowers might be a nice gesture if you can't be there or just to remind them that you are proud of them. If you are curious as to what the flower that is associated with each sorority check out The Sororities section of the web page and click on the appropriate chapter.
http://students.washington.edu/~panhell/
http://students.washington.edu/panhell/AnswerP.htm#note