Answer: Blue Prince and Blue Princess hollies will reach 12-15 ft in height with a spread of 8-10 ft so they will make a great evergreen hedge for your landscape. They are considered moderate growers ( 4"-6" avg per year ). If you want berries, plant both Blue Prince and Blue Princess hollies. If you don't care about berries, plant either Blue Prince or Blue Princess. They both have the same rate of growth and mature size.
Best wishes with your landscape!
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