The day of the wedding, all guests have free admission to explore the arboretum anytime between opening (9a.m.) and the ceremony (5:30pm), you will just need to mention the wedding at the gates. We both love the arboretum and have been going for years, both when we were kids, and again later as dates ☺️ Some spots we love include the walking path around the lake and the fragrance garden. If you don't want to stray too far from the ceremony and reception spaces, we recommend checking out the hedge maze (and the lookout deck in the middle!) which is in between the two areas.