Question
what kind of tropical plants can be grown outdoors in New Jersey?

Answer
Hi Al,
Thanx for your question.  I live in Kansas which has major extremes in hot and cold.  New Jersey tends to have a much more temperate climate than we have here.  I grow a lot of tropicals.  They enjoy our hot, humid Kansas summers (often over 100 degrees) as long as I keep them watered.  I keep my tropicals in pots and then store them in the basement in the winter under lights.

Here's what I grow that you can grow in New Jersey.  Hibiscus, Blue Potato, Ginger, Banana, Oleander, Palm, Brugmansia, Moses-in-the-Bulrushes, cactus, frangipani/plumeria, citrus, coleus, croton, and tons of other things. Al, any tropical will do well in a climate that is frost-free.  I keep my tropicals out from mid April to mid October.  Your season may be longer.  I do watch the weather reports at the beginning and the end of the seasons to be safe.  I hope this helps.
Tom