go to the nursery. Maybe you will have to check few if you want something different. I don't know the nurseries at the north coast. In Sto. Domingo they are so repetitive. There is a good one at La Romana "Anna Costa Nursery"
If you have a small garden, and there is enough sun, look after climbing shrubs. Go for strong colours, pale ones look so sad above the tropical sun (thus dominicans seems to like them).
If like them, you can try orchideas, they are so simple to grove and there are for sun and shade as well. If you have trees or palmas you can put them on the trunks.
Check the gardens in the town, if there is some beauty you don't find at nurseries ask for a "pedazo", put it in water and wait... or ask where they bought it.
good luck!