perahaps a willow hedge would work they are very drought tolerant. I doubt a thunja would be able to grow in such a situation. If it does it would end up being stunted.

you are asking about conifers.. there is a conifer forum.. should you wish to learn more about such .. i do not care where you post, otherwise ...

you will find a lot more info.. if you start using the latin names.. instead of common names ... link below to Thuja occidentalis 'Smaragd' .. which is the real name of the plant you are asking about ...

MOST size estimates are at 10 years ... research the annual growth rate .... and you will find that is what the size is based on ... most keep growing at the growth rate for years after 10 years ...

i dont think it will fit your needs ... mine just dont put on height that fast ...

copy/paste this:

http://www.google.com/search?q=thuja+smargard&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a#sclient=psy&hl=en&client=firefox-a&hs=eXC&rls=org.mozilla:en-US%3Aofficial&q=Thuja+occidentalis+%27Degroot%27s+Spire%27&aq=0amp;aqi=g1&aql=&oq=&pbx=1&bav=on.2,or.r_gc.r_pw.&fp=58aca0ee2c0ec6ed

in a small yard ... it is much thinner but will have the height ....

to fix this problem ... you most likely need to move away from what the bigboxstore offers ... maybe they will have what you want.. but you might need to spend money to fix the issue ..

good luck

ken

Here is a link that might be useful: link

How fast do the Hetz Wintergreens grow in comparison to the emerald greens?

It sounds like you are confusing two totally different species.

GREEN GIANT *WESTERN* ARBORVITAE
and
EMERALD GREEN AMERICAN ARBORVITAE

Green giants are good for about 2 stories of eventual screening.
Emerald green arbs are good for only about 1 story of eventual screening.

To answer your question--the Hetz wintergreen will be the faster grower.

It will remain "relatively" narrow and has the bonus of a single leader---something you will appreciate if you get snow where you are.