Question
i live in the Caribbean  not in Florida area but in Haiti ,we do not have the same sandy soil,i used to  grow roses from Florida, but they lived like 2 3 years and not quite well ,few flowers ,and blackspots ;there were always  a disease
i am not in the mountain where they grow better.i would like to know what to do to obtain beautiful roses in a rather very warm region, thanks for your concern, best regard
Marie

Answer
If you are talking about modern hybrid tea roses, there are none that will do really well in high heat as none are drought or heat tolerant. Reds, oranges and lavender roses are more susceptible to heat stress so plant these on the east side where they only get about 6 hours of sunshine preferably in the morning. White, light pink or pale yellow seem to enjoy high heat more. Roses have bloodlines the same as humans and some roses will do well in warm areas and others do better in cool climates. If the climate is not to their liking, then they go under stress and you get diseases such as Black Spot. Some roses actually like lots of warmth, others only do well in cool climates. So it is the actual cultivar that makes the difference in how well the rose plant does. Sometimes because of your climate plus soil, you have to select logically instead of what appeals to you. For instance, Noisettes, Teas, Chinas, and Hybrid Musks don't complain as much as the other classes.
Mulching roses is a real wisdom where temperatures are hot as roses hate warm roots and want cool, damp ones and a mulch gives them those conditions. Fertilizers should only be given at half strength and only used twice per growing season or use a slow release such as Osmocote 14-14-14. Gardeners really can't expect roses to do as well in high heat as they would in other temperatures and pushing them to perform all summer like one does in cooler climates, will only make the rose go under stress. Because of conditions in my area, I can't grow many of the roses I want to without getting problems, so I grit my teeth and settle for ones that do well in my climate.
http://www.theoldrosarian.com/