The 花 that Nathan gives Haley and is commonly associated with their first wedding site is known as Aster. It can be found in well lit areas that have lots of water around, and needs some type of air flow, so it makes sense that it was associated with a 海滩 type environment. This 花 is symbolic of love, contentment, and patience, which is symbolic of the relationship that Haley and Nathan have shared since the very beginning.