In my area the emerald green is planted about 3' apart. Based on that I'd say you should come back and plant between the existing plants. If the plants are small, I'd dig up the ones that are spaced 8' apart and place them at 3' intervals so that spacing in the whole row is 3' apart.
(Others may suggest different spacing for your zone.)

I used 8' spacing for Leylands that I planted 12 years ago, but if you could see the Leylands now you'd see that the spacing should have been at least 15'! We ended up removing one Leyland that was too crowded.

i would not have used EG in this situation ...

put in a second row of plants ... half the distance of the spacing ...

and i would use anything but more thuja ...

i would also consider.. making these.. single leader plants ... it will be shocking .. but it will be best for the plant ...

the PENCIL holly will accomplish nothing in regard to the site block.. its a pencil ...

since they are only in the ground 6 weeks ... i might move some of them in sept ... bringing the spacing in closer ...

an alternative .... if GGiants will live in your area.. i suggest one.. planted in the middle of the 5 or 6 foot spacing ... they can be had at a foot tall for very cheap .. mail order... at places like botanyshop ... of course.. this is more thuja ... lol]

ken

If you have deer they love Emerald Greens. EG's are are slower growers and relatively small and narrow trees.
Green Giants are deer resistant here in my area and grow much faster, thus get taller and wider.

Come October, I would move the EG from the part near the closest house and use them to block the view in another area where less height will work. Planting then in a staggered pattern, like
existing row: EG - EG - EG - EG
the new row: - EG - EG - EG

And then plant Green Giants in the now empty area.
If you don't need dense evergreen screening year round, you can plant something deciduous as a second row in some spots to add some extra interest and break up the view.

In North Carolina, you can also plant holly (not Nelly Stevens if you have deer) to break things up. Dragon lady is a smaller choice that has the nice conical shape.

Cryptomerias could be another option. Deer avoid them.

This post was edited by wannabeGardnr on Tue, Aug 19, 14 at 15:45

wect,
Wit til the end of Spetember and replace the Emerald Greens with something else.
They grow slowwww. Really slow. Nice color, but OMG, you will be moving, literally, before they even get 5 ft. tall.
You can plant them somewhere else, just not as a privacy screen.
Green Giants are wonderful, hardy big trees for privacy.
They keep their color pretty good in the winter, at least here they do, and they grow ALOT faster then EG.
Tee Olive trees are an option, just ask a local nursery, Privately owned nursery, what grows well in your area.
They will tell you what to use, so you have a privacy fence in your lifetime.
They look so cute, but don't dig them out til it gets colder.
Transplanting in the heat is VERY bad for conifers, and in NC, it can get hot.

Thanks everyone