I wish. I have two x 960 LED colour changing trees. They have been outside for at least 3 if not 4 years and the blossoms are all brown.
Surprisingly it doesn't seem to affect the colours too much when the tree is lit and the brown ones almost look more real during the day time. Having said that I'm sure i would notice the difference if I put a mix of old and new on there.
I haven't tried it personally yet, but I've been contemplating using a clear UV resistant spray on my pixel modules. Maybe someone else has experience with this??
I was thinking Spar Varathane.