What about Blue?

 

trout

Color vision is a well-defined trait in shallow-water fishes as a mechanism to allow the fish to better separate potential food items from the background. As such, flies or lures with strong coloration and/or a lot of flash--which makes them stand out strongly against the background --are great fish attractors. Trout see every color we do, plus they can see infra red and ultra violet.  As such they are seeing colors that we don’t which probably explains why blue flies can be very effective.
Some time back Larry Jurgens was talking about how effective blue Ultra wire flies could be.  So I tied a few Copper Johns and some other patterns using blue wire and/or dubbing.  I found that it not only produced fish but could be a preferred color on some streams.  Give it a try.