Answer: It would be easier if you had provided the names of your hollies, but since you didn't, we can almost guess; male hollies typically have male sounding names (Blue Boy, Blue Stallion, Blue Prince, China Boy, Mondo, etc.) and females usually have female sounding names (Blue Girl, Blue Princess, China Girl, etc.). The males will not produce berries but the females will, providing there is a compatible male holly nearby.
If you still don't have a clue as to what you're growing, examine the flowers on both your hollies. Male flowers typically have longer stamens; female flowers have a slight swelling at the base (the ovary). If the flowers on your hollies are different, you have both a males and female hollies. If the males (those that are not producing berries) are flowering at different times than the ones that are producing berries, the males will not act as good pollinizers for your females. In this case, you'll need to have the plants identified so you can choose the most compatible pollinizers for them. Sometimes knowledgeable nursery staff can help identify the plants by examining the leaves and the open flowers. You might also try taking a flowering branch into your local cooperative extension office for help in identification. Hope this information is helpful!
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