25 years ago. i had a lovely mint patch in the corner of the yard at my house in Hanalei (kauai), It did decide to take off. It indesperced with the the lawn. For many years when ever i mowed the lawn it smelled of mint. It was wonderful. i still see tufts of it pop up here and there in that yard.
Mentha piperita can be grow here in Atenas. It is a a ground cover. Needs humidity all the time and shaded area. It grows well near a creek.
Average temperature here is 26 celsius, humidity almost 80%. We have a dry and wet season.
Welcome reninja! There are about 74 members in DG that are from Jamaica...so I'm sure that they would be able to help you figure out your zone. I would suggest that you start a thread entitled something like - Looking for fellow Jamaicans or something. We are happy to have you here in the Tropical Gardening Forum...a nicer bunch of folks you would be very hard pressed to find.