Matthew Williamson dress goes from blue to green and the print gets larger towards the hem. It also has a really interesting back.
Thalia Sodi dress apart. It would be perfect for a nice dinner in a beach town and it would still fit in on the boardwalk.
Liz Claiborne pants. I like the pants are a little wide but not outrageous; I think that amount of flare works really well on a petite frame and it has elastic on the back to keep the fit nice.
New Look jumpsuit is awesome. The palm print is bold the shape is very streamlined so it looks chic.
Here are a few more tropical options.