Does it need a pollinator? Some plants need a mate. Could this be the problem?
Suzi

I think it just needs more time. They're supposed to take about 3 years. Any reason why yours dies back? I got one a couple of years ago but left it in a corner where it was shaded and just ignored it. Hasn't flowered or fruited yet. Just a month or so ago I took a cutting from that plant and placed it in a better spot with much more sun. It's growing really well and none of the plants have ever died back.

it has a weird tinge to some of the leaves. maybe not dying back, but it had a growth spurt last year, shed some leaves, and hasn't really done too much since. I would think it would send runners and other branches

It's winter here now and my cutting is still growing, though not as fast as at first. How is your soil, and drainage? Perhaps it's a bit waterlogged in a heavy soil. Mine gets plenty of water but drainage is very good. And the cutting is getting a lot of sun.

south florida has sandy well draining soil. i was wondering if it isn't rich enough?

I'd try getting some good compost around it. Sandy soil doesn't hold anything, not nutrients, not water. My soil is pretty bad but it's more of a lateritic fine gravel. Not much better than your sand, but with a high iron content.