Hi - you haven't said a word about how it's living - how often does it get how much water, how much sun, and what about fertilizer? Need something to go on here.

Lucy, fertilize twice a year, high N in spring and high P, K in fall, full sun. water once in spring, fall. twice in summer. higly drainage soil. Zone 9, Houston, hot and humid in summer.

Andrew... "water once in spring, fall. twice in summer." - Please tell me that's a typo - your tree would have been dead LONNNG ago otherwise :-). Or is it a real live tree?

Lucy, I meant water once daily in Spring and Fall, twice daily in summer.

About the only thing I can tell you from here is that many people's trees this year did not put out leaves when expected (or even at all), and we're putting it down to global warming, or at least weird weather in general, for now. As yours may(?) live outdoors down there a lot more than ours, it may be reacting like an 'outdoor' tree vs the hothouse tropicals we treat them like, or going through its own little dormancy, though that seems pretty far fetched considering. Sometimes you just have to put things down to genetics. Try rooting a cutting and see what happens (and let us know).