two possibilities (or a combination of the two):

1) different varieties
2) nursery trees have a head start in the greenhouse.

~james

The growing cycle for both figs will get synchonized by next spring and the only difference left will be based on the fig varieties.

tfalsetta, Your old tree had figs Aug.-Sept. Those sound like main crop figs produced on new wood.
If your new tree is popping figs on old wood produced last year, it is a breba (or early) crop and the new fig tree might produce two crops for you - breba and main crop. If the brebas stay on the tree - some varieties drop brebas.

Nurseries tend to be better at keeping the plants happy (its their full-time job after all) and so your new plant was very happy there so is showing its happiness in delayed fashion - those figs were set as the tree went dormant. I had some trees do that and then not produce another fig for several years. There is also a large variety difference. In my main planting my youngest fig is now setting the biggest breba crop I have ever seen.

Scott

Mulch, mulch, mulch, mulch with composted maanure especially if you are growing in pots and you will get fruit.