as you have learned..trees ... aka conifers.. never really stop growing ....

most size estimates on the better sites ... are at 10 years ... and you can probably bet.. they will be double that.. in 20 years ...

yes.. location makes a difference .. consider my MI.. where the ground is frozen solid for at least 3 months .... as you can imagine.. things dont grow then.. lol ...

the real key to look for.. is annual growth estimates ... you can find them.. if you use the latin names ... and try hard enough .... so.. if a tree grows 1 foot per year ... in ten years ... 10 feet tall ... if 3 feet per year.. etc ...

i have done such here for you ....: https://duckduckgo.com/?q=Juniperus+chinensis+%22Spartan%22+annual+growth+rate&t=ffcm&ia=web

somewhere down that link.. you will see the annual growth estimate ....

i would highly recommend not planting all of one kind of plant.. just in case some plague comes thru ... i have no clue about your NM ....

distance apart is a personal decision .... if you want a solid sight block ... you plant them closer together.. and let them intertwine ... if you want individual specimens ... further apart ... when you can define the goal.. the distance decision becomes much easier ...

ken

http://conifersociety.org/conifers/conifer/juniperus/chinensis/spartan/

Thanks Adrian! Good thoughts and thanks for your pointers. Ah, more to think about...!

btw .. as to width ... its a proportion of height ... so its hard to give any type of definitive answer to that question ...

if you look at the link below .. you can sort of see that width.. looks about 1/3 of height ... but some of the pix seem to show sheared plants ....

ken

https://duckduckgo.com/?q=Juniperus+chinensis+%22Spartan%22+&t=ffcm&iax=images&ia=images

That's perfect, cearbhaill! I wonder why that thread didn't come up when I did a search? Now I'm trying to decide between Spartan and Torulosa. Most of the photos on the web show Spartan sheared into a cone. I'd like a slightly looser look, but I don't know if Spartan will do that if it is not sheared. I wonder if it depends upon the climate as well. J. scopulorum 'Skyrocket' when grown here doesn't look like the ones on the web, being much looser and wider than those shown, and 'Moonglow' as grown here, looks like a lumpy blue muffin to me, and tends to look rather scraggly. 'Wichita Blue' is male, and is illegal to plant here (pollen producer). People don't pay attention much to that restriction, but I'd rather not have the extra pollen next to my house anyway, but I think 'Wichita Blue' is quite beautiful. I was mainly looking for a background for my rose garden, since I'm taking out some unhappy and misplaced Colorado Blue spruces, and an English hawthorn that has skewered me too many times. So I need something tough that can handle this dry and windy, hot summer/cold winter climate and I'd like something evergreen. Now that I'm looking, I'm seeing all the exciting options. Recommendations/suggestions?

We went with 5 feet exactly with our row of Spartan Juniper’s and after 3 years they grow together perfectly without being too crowded.