Just so you have a good idea, in my cemetery I use four blue floods as well as a purple and an amber and that area is only 16' x 48'. You may need more. Of course, it all depends on how subtle/extreme you want the amount of light to be.
Blue puts out a pretty weak amount of lighting too, so keep that in mind. Red and amber put out pretty good amounts of light per watt.
Blue puts out a pretty weak amount of lighting too, so keep that in mind. Red and amber put out pretty good amounts of light per watt.