BOTTOM photo is standing at the slider and looking toward the left.

If you put those together it's probably missing a small section of more just bricks section...there is only that one pillar back there along all that wall.

AGAIN, on the other side of that wall is a fairly busy-ish road and there are more houses back there now than when I took the pics. I want to screen out the noise (I know that doesn't always work but it's gotta at least soften it!!!) and I'm not super keen on seeing all that stuff back there out of our second story windows. SO I'm interested in things that keep their leaves all year (that's why I'm leaning towards bushes and not trees).

i would be much more diverse on the planting ... than one or two types of plants ....

and.. anything FAST TO GROW ... is usually fast to lots of pruning ... choose based on proper plants ... not how fast they grow ... there isnt really instant gratification in the garden ...

you max height... will be determined by you ... and your ladder .... and how comfortable you will be cutting things on top of such ... e.g. if you want 15 feet .... that would mean a 12 foot HEAVY ladder .... and you using tools on it ...

you are putting yourself in a box... by insisting on working only at the wall ... two of three evergreen trees... say in the middle of the lawn ... could block out a lot of linear feet at that wall ... think outside the box you are in ...

sorry ... no clue on plants for CA ...

ken

We are not putting trees in the middle of the lawn. Especially not evergreens. That's silly and would make the yard unusable. We didn't buy this big of lot to make it a forest of trees and no usable space for family fun in the yard.

Furthermore, I would plant other things in front of the bushes, but as a base for planting, I'm looking at what to extend the height of the wall with. I can plant other things as they fit in front of them.

Still looking for ideas on what shrubs or trees might be a good use there besides the ones the nursery briefly suggested.

You don't seem to be getting much joy here, so you might want to search the California Forum which seems fairly active. I went to the CA forum and did a search in the top box "Search in GardenWeb" with the word "shrubs" and chose the option that popped up for limiting the search to the California Forum. Here's one thread that popped up that might be useful to you. I didn't check beyond that, though there were many other threads that looked like they might help, but often a search will give you a bunch of info that pertains to your situation.

Since you know your situation best, it helps if you give as much information as possible, such as you want to have the center of the yard available for family activities (as you stated two posts up) or you have a dog that likes to patrol the border or . . .

A few general comments:

If you use a mix of plants with clusters and repetition of plants along the wall, it will give you some variety and if one plant dies, you don't have to search for an exact replacement since there is already variety in the mix. I wouldn't do one huge block of one type and another huge block of another type - that always looks awkward to me and has the same issue of replacement as well as if a disease takes them all out, you are left with nothing, whereas a mixed shrub border rarely all dies at once.

Consider small trees with branches that will reach above the wall as part of the mix to vary the height so that it doesn't end up feeling like a fortress of green. You might also want to consider vines on a trellis along with shrubs and small trees.

Trust me, plants really won't add noise screening, though your wall will; I just want you to have realistic expectations. (I live in the boonies where in places there is something like 1/4 mile of woods between me and traffic, and noise decreases due to distance but not any different due to taller plants vs. open field.) If you can add to the top of the wall, that will improve sound screening a bit, or you can add ambient noise to your yard that may distract, such as a small water feature with dropping water (perhaps not appropriate in your arid climate) or plants that rustle when the wind blows. The plants will provide visual privacy, however, and that seems to be your main focus, and will add appeal to the wall from both sides once they reach over the top.

How far to put them away from the wall depends on several factors, including how big the wall's underground foundations are; how wide the shrub is supposed to get (take half of the shrub's reported width and since this is given usually at 5-10 years, add a couple of feet since it will usually get larger) and this will be the distance from the wall to aim for; and how much time you want to put into pruning in order to maintain that width. It's a long stretch of wall, and it sounds like you have a family, so you probably want to choose something that doesn't need a lot of trimming.

Another maintenance thing to consider is water. Since many areas now have watering restrictions in CA, I'd plant things that will be OK if you can't water them at all for a season. They will need water the first season while they establish, but after that should be able to survive without.

Plan on using mulch (I am not sure what type is appropriate for your area, since although organic mulches such as chopped leaves or shredded bark is most appropriate here, I often see inorganics such as gravel used in low water areas.) Ask on the CA forum once you have your plants chosen which mulch would be best in your area. Mulch will help reduce weeds and increase moisture retention.

Good luck. I'd love to see what you end up with.

PS - I'd also add your location and zone to your profile so it posts along with your name. That way everyone knows where you are before opening your thread, and you may get more helpful responses. Here's how:

Go to Your Houzz in upper right of every page, click Edit Profile, and on the left side click advanced settings. Well down the advanced settings page is a blank labeled Climate Zone for Garden Forums along with a link to find your zone.

If you add info on your state or the nearest large city you will get even better information since zone only relates to average coldest winter temperatures.

Then return to the top of the page and click Done Editing.

NHbabs, I hope you see this because I wanted to tell you that I found your thoughtful reply very generous, and you also helped me with a somewhat similar issue.

Thank you Dave! I have no idea why the site did not notify me of replies like it always has in the past. I was delighted to come here and find many great suggestions. I will write them down and take them with me to the nursery to see what I can find and find out about how they do here. I appreciate your help. :)

NHbabs, thanks for your input too, I'll check out the CA forum. :)