Washington Navel oranges ripen in the winter, like most other citrus. Yes, your little oranges will be ready between November and January to enjoy. And no, citrus for the most part do not produce successive crops (with the exception of a few, such as Improved Meyer lemons, and most kumquats). If you would like oranges more year 'round, consider planting a nice Valencia orange, which is ripening now. Be sure you're watering appropriately, water once or twice a week, a long soak, no overhead sprinkling but on drip or micro-sprinklers, have no grass underneath the tree, keep the tree well that should be created at the drip line (edge of leaf canopy) mulched, but keep mulch 2 to 6 inches away from the trunk, and fertilize every 2 to 3 months, from Feb through Oct with a good citrus fertilizer that contains micronutrients.

Patty S.

Here is a link that might be useful: UC Riverside Citry Variety Collection: Washington Navel Orange