Exactly Odinson...parish to parish...even yard to yard.
If you Google the seasons for fruit & veg in Jamaica, you can get a decent idea of what you'll be able to purchase when visiting.
In our yard, we have a famous June Plum tree that blooms the " wrong" time of the year...making it popular.
A Star Fruit tree that blooms (thankfully) too often!
Five different types of mango trees...that keep us supplied almost the whole year. A Nasberry tree & Sweetsop that blooms late spring....breadfruit & ackee over the summer months. Generally, you can find breadfruit & ackee all year long.
My fav fruit to get from the beach vendors is guinep. You can find this small fruit over the summer months & sometimes lasting until late November. If you've never had a guinep...don't be shy to ask the vendor to explain to you how to eat it.
There's so many more wonderful fruit & veg choices...though they may have been harder to find on the beach for purchase lately, as it hasn't been viable for vendors/farmers to bring them into town the last couple of years.