I love going to blossom. Truly I do. But I was so disappointed with my most recent experience there. I felt that the staff was rather rudely enforcing regulations which are not clearly delineated on their website. Just to clarify for future concert goers: for any concert aside from the orchestra concerts, you cannot bring any outside food unless it is in a one-gallon clear zip lock bag. No beverages except for closed water bottles. I'm not opposed to these regulations, I just found it frustrating how they were strictly enforced even though they're so unclear on the website. Here's hoping that their website gets fixed.
As long as you're aware of these rules ahead of time, it's a very pleasant experience. Be prepared for a great concert, preceded and followed by so much traffic. But it's worth the trip :)