One of the pleasures of late fall field work in the low lands of western Washington are the tasty treat of evergreen huckleberries (Vaccinium ovatum). November to December is when these berries are at their peak for flavor depending on the weather. They tend to get grainy after a hard freeze, but otherwise hold their flavor better than other berries perhaps because they reach ripeness after the weather becomes very cool.
The plants are evergreen and are described as liking moist partial sun areas with acidic soils. My own observations are consistent with the above, but I would note they do best in places that have a period of drought and are located in soils that dry out at least for a month or so. Hence, the plant grows thickly in northeast portion of the Olympic Peninsula and often is associated with native rhododendron. I have encountered impenetrable thickets of evergreen huckleberry on the Toandos and Bolton Peninsula. The berries above were picked on a forest edge near the south end of the Toandos.