Only thing i can think of is Skyrocket juniper. Its very narrow and can take the sun and some heat, is low maintenance. I think it can benefit from a loose, well-drained soil.

Thanks for the juniper suggestion ... I'll send it along to my mother. It looks like a very attractive option! Question: my own experience with other (much wider/larger) forms of juniper at a previous house was that they seemed prone to unexpected die-out -- sections would just abruptly die on me. (I'm sure there was a cause, but not an obvious one.) Does anyone have experience with Skyrocket in this respect? Is it a pretty solid performer?

Well, my first thought on reading the beginning of this post was pyracantha. Given the size of the space, is it possible to bring that over a bit more and cover it that way?

The problem here with Skyrocket is that heavy, wet snow bends it over. Down there it isn't snow but ice.

Hi Mad_gallica,

Yes, we thought about trying to coax the pyracantha over a bit farther because it really is large and beautiful (there are two of them on this wide brick end wall). But the utility boxes my mom wants to hide are quite far from it so it wasn't clear how effective that would be. She really liked the idea of having her "own" plant (it would be right around the corner from her entryway so sort of "hers"). She currently has a Queen Elizabeth rose bush which is nearing the end of its useful life (it is QUITE old) and which is requiring ever increasing amounts of labor (spraying, deadheading, etc.) to keep it looking like anything. Hence the desire for something evergreen (so the boxes will be hidden year-round) and low maintenance.

I had read some posts about Skyrocket suffering from snow weight (ice would presumably be worse) so that's something to consider... thanks for raising that point!

So... I need something vertical, evergreen, TOUGH (can take ice buildup), and narrow in diameter so it won't block the sidewalk ... hmmmm. Something trellised against the brick seems the most logical, but what, if she doesn't want to compete with the pyracantha?

Check out Sky Pencil Holly (Ilex crenata, or Japanese Holly, selection) and Graham Blandy boxwood. Both very upright, very narrow and to 8 or 10 feet tall; you could plant three next to each other for a nice screen. I'm in Maryland just outside of DC, both thrive throughout the greater DC area. Given the location between the wall and the sidewalk, she would have to be pretty diligent about watering the first couple of seasons, but, once established, both of these would need minimal care.

- Steve

'De Groot's Spire' arborvitae might also work - mature height of between 12-15' and no wider than 2.5'.

Thanks to you all -- Mom has decided to order a Skyrocket juniper and give it a try. I myself liked the boxwood option -- there's a lot of boxwood in the Alexandria area and it would certainly fit the Colonial look and feel, so that's a fallback if the juniper doesn't work out.

I thank you all for the responses! (She does, too!)