There could be several reasons. Fuji is mostly a tip bearer apple. If you " trim" off portion of branches, you prune off the flower buds. If Fuji blooms later than the other two, it could be pollination issue. Just a couple of examples.

Oh my, that's an especially beautiful example of this clone. Great find! Gotta love that feeling when you can cross one off the wish list (it just makes space for a new one, hehe).

This spring my apple tree did not blossom or leaf out as it usually does. The leaves are sparse and folded inward. Many of the blossoms are black. I do have some apples on the tree but not nearly as many as usual. What is the problem?

Sorry, but the two issues are not at all the same!! Rick, your apple blossoms are just showing some weather damage......nothing to worry about and nothing to treat. Fwiw, a great many early blooming trees and shrubs will produce flowers that show this sort of damage....typically just the result of a heavy rainfall. We see this all the time in our wet PNW springs......and we grow a heck of a lot of apples here in WA state!!