Visit first... Connect with locals and get a feel for how you could add value there... Maybe start a partnership with someone there...
When I was in India many years ago, locals asked me to start an import/export business... Perhaps that is something you could do in El Salvador? Happy to help you sketch out a business plan....
Some foreigners who move to India started restaurants in their homes, serving local cuisine (this was an Italian couple) ... after weeks of eating Indian food, we tourists were happy to have some amazing Italian food!
There was also a couple who bought a farm and did a farm to table restaurant and sold fresh produce to the tourists who were there for months and were seeking organic options and more international food.
So these ideas may apply to El Salvador and the growing community of foreign visitors.
Also, could possibly sell your gardening business if you decide to make the move... Or run it remotely?