so...you were a little concerned about getting answers in conflict...so you come to the nexus of consensus...yeah, that's gonna end well.

size under conditions...this includes prevailing winds in winter, which also gets to the use of anti desicants. If you are in a situation that would lend itself to a wind tunnel, such use might be beneficial. That should get the agitators going.

In general, rate of growth and ultimate size are going to vary depending upon time frame, soil and weather conditions, fertility, care...so any answer is subject to more legal disclaimers than a heart transplant. The Princess is likely to get taller than the Prince, and in such a short space, might look funny. Speed? I doubt they'd ever grow a foot a year, maybe average half that over time, maybe a bit more. Ultimate size no trimming? Perhaps 10-12, perhaps closer to 15. Then again, maybe 8-10. It all depends...

Male female ratio...think of it a harem...one male goes a long way...like one to eight to ten to twenty.

Spacing...the faster you want them to fill in, the closer you put them. These guys are going to be slightly taller than wide, but you were generally right. They'll grow in all directions, kinda like Uncle Phil at Thanksgiving dinner. I'd be hard pressed to suggest putting them closer than 6', probably closer to 8. But that's me. Feel free to ...need a good word here...one that implies conflict and lack of agreement...should we say dissent?

now for the real kicker, and my view is going to be different than some here. 6' plants to start? in blue holly? You can find them?

If you have the budget, go for it. Most folks that frequent these forums have a set of priorities that is different, but that's them. If you want size (I assume for privacy) and can afford it, go for it. Everyone has their own priorities and finds the reason to support their view. But that's what makes the nursery business an exciting dynamic place. Some people want large, some people want small and infinite variety. Both can be satisfied. Just think how boring things would be if this were not the case.

But really...you can find 6' blue holly? I guess I'd want to know more. 6' is typically a size for arbs, spruce, or American holly. a more typical size for blues is 5g 18" or 7g 24".

I can't speak to your conditions, but I can show you Blue Princess hollies that I purchased at a similar size. If memory serves me they were $150 each, but my memory is crap, so who knows!

{{gwi:249195}}

This was them a couple of years later.

{{gwi:249197}}

And that was four years ago and they still kinda look the same.

Mine are in dry shade with tree root competition so that is totally different than your conditions. I did a lot of TLC in the early years, but now they are pretty self-sufficient. Mine grow very slowly and openly but that is due to the shade no doubt. But yet, they still manage to make a good deal of berries. I have one small boy about 15 feet away. My spot gets a 3-4 hours of morning sun.

As I look at that first picture, I wonder if the one on the left got moved a few feet to the right after that shot was taken. again, memory... crap. I wasn't looking for a hedge, just a partial buffer.

I would definitely not plant the boy(s) in the same hedge. I would also plant another girl somewhere else on the property as insurance in case of a loss.

As far as height, I suspect they will grow indefinitely, slowing down with age, but you can certainly keep them pruned them at the desired height. If a tag says 10-12', they don't really stop at that size.

I would get 5 and plant them 5' OC

Your soil may not be acidic enough for optimum growth. You may need to amend.