4 x 2.5 feet after 5 years, ultimately 13 feet high - if you don't clip it or keep it in pot.

or box common ' tree ultimate height, in ten to twenty years 30ft (9m ) hedge height 1to 9ft avgrage groth 4 to 6inches per year, thats upward groth but the weeping nature means it will grow a lot more, hope this helps.

sorry Bamboo we were writing togather and as usual you beat me,

Doesn't account for the difference in the eventual height you've given compared to mine - where did you get your info from? My book says 13 feet or 4 metres for full height, not 30 feet. Unless you're thinking of something different, because B. sempervirens doesn't "weep", its quite upright.
PS - just checked online, and one site does say it gets 30 feet - but I'm sure it doesn't, well, not in a lifetime anyway.

there is a hedge and also atree and the hedge weeps and although it grows as much as six inches only up weeping branches grows more, I will have a look for the site and pm it to you.

should be there now Bamboo

I suggest a visit to Box Hill I think it is in Surrey. I suspect that the ones we gow in our gardens are from selected dense growth varieties and may have great differences in growth rate even if they look the same when young. I find the Buxus sempervirens itself grows about 8 inches per year, but this is poor dry soil and perhaps would do more than this if well fed and watered

As Poaannua says, visit Boxhill, It's about 10 miles from us. I have not been up there in recent years but there are many trees which are 15 to 20 feet high, many are blown over. We have lived in this area 50 years, they have not planted any new trees for some time. On one large property I worked on I put lights up for Christmas on one which was 15 feet and about 100 years old. The wood is used for mallets.

Well I guess that confirms that 30 feet is a bit extreme, then - 100 years old and 15 feet high makes my encyclopaedia's estimate of 13 feet ultimately (in a human lifetime) look about right then.