Green Giant Arborvitae Advice

 I'm thinking of planting a hedge row of Green Giant Arborvitae.  I
want to plant them tight (3 foot on center), because I don't like the
V-shaped gaps I've seen on other Green Giant hedge rows planted to the
"recommended" spacing.

My other plan is to keep them sheared to a rectangular envelope 4-6
feet deep and 12-20 feet high.

Does anyone see any problems with either of these plans?

Thanks.

 edit:  I might even try 2 foot  spacing on center.

 mike wrote:

Your neighbors are really bugging you, eh? LOL

 
I might rethink that :-) 'Green Giants' are hybrids and only
tangentially related to standard arborvitae (Thuja occidentalis).
Their typical spread is more closely related to Thuja plicata (one of
the parents) and can reach 25' - they are not by habit columnar and
narrow in profile, but rather more of a 'Christmas tree' shape - more
or less conical and broad at the bottom and with a tapering tip. Too
close a spacing will result in heavy shading and die out of lateral
branching and you could end up with a very spotty looking privacy
screen. Recommended spacing for a dense screen is 5-6' o.c.,
otherwise, 10-12'.

 
I understand, but don't all hedges have lateral branch die-off due to
adjacent neighbor shading?

Also, from what I've read, they can be trimmed to any shape (i.e.
rectangular) even if they would tend to be a tall cone if left alone.