Ligustrum makes a good hedge, but the ones that I am familiar with require trimming at least twice a year or more to look neat and stay in bounds. Common Privet escapes cultivation and is a pest in many areas, so please check with your local County Extension Office and ask about invasives before selecting a shrub.

I'm not familiar with zone 9 plants, so can't suggest other plants.

Finer leafed evergreens such as Pittosporum tenuifolium cultivars or Syzygium paniculatum are probably better choices for dense narrow hedges, but both, along with the Ligustrum will require shearing at least 3 to 4 times a year. You could also use fast growing scandent shrubs such as Tecomaria capensis, which lends itself very well to hedging. Heavenly Bamboo, Nandina domestica would also lend itself to being used as a 6 foot hedge, and would need much less pruning over time.

How about a different idea entirely? I'd be inclined to make a nice lattice fence (not the cheap, tacky, flimsy stuff but custom-make something sturdy and attractive) and then grow flowering vines through it to give screening and color. That would give you the narrowness you need. Your privacy initially would depend on the spacing of the pattern you picked. Look around at lattice patterns and see if you can find one you like. Oriental or middle eastern screens might provide inspiration for something more attractive than just a square or diamond pattern (although a good quality simple study one would be nice too...)

All very good ideas. I'll examine these and make a decision. Thanks very much.

My garden is divided into many smaller beds, most of them fairly narrow. I agree with woodyoak about the trellis and vines. You will get better coverage without giving up depth in your seating area.

There will be some maintenance with the vines, but not nearly as much as the trimming of a standard hedge.

Make sure you have a sufficiently sturdy trellis. Don't overplant the vines - it's a temptation to try for early coverage - but vines really spread out and up. Crowding your plants together will create an ungovernable monster whose weight can easily crush any shaky wood underpinnings.

It would be pleasant to plant different types and colors of vines, for a coordinated but varied look. The eye gets easily tired when it's a solid green wall of similar color/shape/texture.

If you are in a low-frost area, most evergreen vines get really big. In my area, one morning glory vine would cover an entire 20' fence in a few years, and just keep going....!

Shrubs like pittosporum and privet get much wider than 2 feet and "pruning" would then be shearing on top and sides over a large area--a big job unless you just love it.

Agree with the trellis or open-block type of wall tends to provide the most space-saving privacy along with neatness and even elegance. If you do some book-browsing and surfing for small space gardens, narrow space gardens, side yard gardens, etc you will find a lot of different approaches by people trying to do just the same thing--achieve privacy in the narrowest dimension possible--and could get a feel for what "look" you'd like.

Also think in terms of combinations--I've seen some "walls" constructed of separated panels with some plantings in between, rather than a solid panel of wall. Or a partial L-shaped wall (I'm using the term wall to refer to some kind of built structure of lattice, open trellis, or other material)anchoring a corner, with more informal plantings extending the arms. And further, if you go so far as to custom-build, I've seen cool "walls" in which the length of the wall formed a pattern combining solid parts and small open parts so that a passerby might get a glimpse, and the occupants glimpse out, but provides substantial shielding. All that depends on the kind of traffic and privacy involved.

A third concept is to know more about what you want to do with the space inside and whether you can incorporate your "hedge" idea or lattice idea into what is to be the garden itself. For example, do you plan to have all of the "interior" space bare, as for table/chairs, or did you plan to have a "garden" of many other types of plants/shrubs "inside" the walls? Because it might be possible for you to consider part of your "wall" of planting to be, in effect, part of the garden you experience from within, and therefore could devote more than a couple of feet to it and more variety. So that area might have some tall, dense and relatively narrow shrubs to provide the privacy, in essence the outer "wall," and then step down "inside" to more intimate and varied plantings, flowers and so forth that you experience when you are within this garden area; or, you might be able to "afford" the space for a larger shrub that earns its keep with flowers, fragrance; Again, perhaps there's not space to do this for the entire "wall" length needed, but might anchor a corner or something and provide variation.

So one thing to think about is maybe to sketch out what you'd like to happen in the entire space and in what exact parts (center, corners, where do you enter, is it connected to the house, will there be paving material underfoot, furniture), and this will tell you something about what you have to work with. This could be started off with the very simple "bubble diagram" doodles to get you thinking. That approach could be an alternative just walling the area in first and then going, now what am I going to do with the space I've isolated? Though of course you might end up deciding that an actual very narrow "wall" structure is just what you need.

Columnar evergreens like Thuja DeGroot's Spire or Taxus fastigiata? Not sure if they'll grow in your zone.
Check the conifers forum - there may be old threads on heat-tolerant conifers.

KarinL