Pollinating Ilex Vert. Winter Red
I just purchased three female plants. I live in an area with lots of naturally occurring holly trees. How can I know if any of them are males that will pollinate my new hollies next year? And while everything I read says these plants will grow to 6-8 feet, can they be kept trimmed to a hedge approximately 3-4 feet without damaging them? Thanks.
Pollination and berry set depends upon overlapping time of males and females, compatability between species, and favorable weather conditions assuming insects (bees) will be present in the locality.
You did not mention what type of hollies (naturally occurring) you are referring to. Although it is possible that holly species can provide pollen to other species there are limits to the type of holly that will produce a consistent display on female hollies.
The best pollinator for any female holly is generally a male of the same species.
Usually one male for every 10 female plants is a good ratio, with the male within 100 feet, or less, of the females.
There are a number of charts that describe specific cultivars for which males pollinate which females:
Take a look at the attached link from Va Tech regarding pruning. It responds well to pruning. However, berry display can be affected in the future. This may defeat your purpose of having fruits. You may have to experiment if you want to keep at a specific height or select another species of plant.