Answer: In order to serve as a pollen source, the male needs to bloom at the same time as the female. The most reliable pollen source for the Blue Girl holly is Blue Boy so to assure berry set that would be the best choice. Blue Stallion is also sometimes suggested becaused it blooms over a long period of time. If there are other male hollies in your neighborhood, you might not need to purchase your own male for the Blue Girls. I hope this helps.
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