Don't you mean a rodedendron?
The trick is... the circumstances have to be the same in the old and the new spot. Cause plants adjust to their circumstances.
So if you can, bring a lot of earth of the old spot, in the new spot.
Perhaps you shouldn't try to place it from a shady to a sunny spot or vice versa.
Oh yeah: give enough water! Not too much... but enough...
Good luck.