There are few truly blue fruits or flowers, perhaps because very few creatures can see the color blue (birds and primates are the most important groups that can). Some viburnums and dogwoods make blue berries, but with most of the these very tasty plants, you almost never see a ripe fruit–the birds eat them the second they ripen. If you look carefully at the photo above, you’ll see a number of ripe blue berries among the green unripe ones. I took this photo early yesterday evening, and all the ripe berries were gone this morning. (The colors and contrast on the photo were enhanced a bit.)
By the way, Cornus sericea is one of the most adaptable native shrubs: in nature it usually grows in very wet places, often in full sun. In my garden it’s growing in dry, sandy soil and almost complete shade.