Most latinos in Florida are not of Mexican descent, and Trump's comments were most hurtful for Mexicans, so that might partly explain it.

Florida's Latino population is unusual (relative to the rest of the country) because of all the people who settled there after fleeing Cuba. It's typical for them to vote and identify heavily Republican based on issues around US-Cuba relations (Marco Rubio and Ted Cruz are both of Cuban ancestry, for example).

There's also the 100k+ who've left Puerto Rico in the last decade. I believe most of them made it to Florida.

http://www.cnn.com/2016/05/02/americas/puerto-rico-exodus/