I tried to grow apples, peaches, pears even olives here.
They grew, yes. In fact the apples seemed to do very well and it looked promising....
But, in the long run it is just not worth it, trust me.
I put a lot of effort into trying this out and spent countless hours of preparing the right soil (PH), germinating the seeds (scarifying and stratification), growing the seedlings, adding natural, organic fertilizer tea and even tried to talk to the little specimens to give them hope and a bright future.
Again, don't waste your time, I already did that to tell you it won't work.
After the first year the peaches just withered, the pears turned brown and then eventually died, the apples did make it to the 2nd season but then they too suffered from the heat and lack of cool weather periods. The olives, well they are still alive but not doing well at all.
dv8 gave good advise...try in a much cooler region, Jarabacoa or Constanza, that's your best bet.
Best wishes,
Reese