Planting a hedge, zone 9 -10

I have a rental duplex on a small urban lot. The white picket fence is falling apart. I'm thinking of replacing it with a formal (rectilinear) hedge. My gardener (my daughter) and my husband think I'm nuts. (Well, they like the idea better than an inward-facing cobb bench/wall. My daughter says there's no way she is building that for me. I don't have anyone else to build it.) I'm in zone 10a; I'm thinking manzanita (native, good for the bugs that are food for the wild birds, small leaves, maybe not dense enough) or citrus (fragrant when blooming, probably thicker foliage, might even fruit, harder to keep tidy, larger leaves) or olive (if I want fruit it needs spraying for olive fruit fly). I'm wondering whether this is the dumbest idea ever in terms of maintenance - I will soon be living far away. Have you ever worked with a hedge? Do you have advice for me? Plant ideas? Are they hard to keep tidy? Would it work aesthetically as demarcation of a small (10 x 30 ish) yard with four small fruit trees and several roses? How tall do I want it? Three feet would be about like the current fence. Four might feel more enclosed. Five starts to be maybe too big for the adjacent sidewalk & would have to be very formal & well kept to not grab passersby like the whomping willow, but would also hide the street somewhat for the residents and might keep the neighbors from picking my persimmons. Or would it just shade & crowd the persimmon and keep it from fruiting? Argh. I figure I have a year to get the plants started before the fence falls down entirely.

I'm not familiar with Zone 9-10, but I have a suggestion for something fast. Most of the options you mentioned would take a while to establish.

There are many decorative grasses that can grow quite tall in a single season (some up to 12 feet). I imagine the seed heads would probably be good for the birds. Not quite as much habitat, but it would provide a privacy screen quickly, and in that zone maybe it would die back in the winter?

A hedge sounds like a fabulous idea!

Pomegranates can make a great formal linear trimmed hedge. You might even get the occasional fruit; though they can look a bit shabby in winter.

A house near my kid’s school has a living fence made of fig trees. It surely took loads of training the main branches initially, but during the winter the trunks and branches form a “fence” and in summer, it’s green and full. Every year they cut the new growth all the way back to the main framework branches. No clue if they get figs.

Citrus probably won’t work well for a formal trimmed hedge, but I’ve seen them planted close together and kept short, the resulting look is undulating and lumpy, but certainly hedge-like.

Elderberries are pretty great for hedge areas. They multiply by runners and have to be tamed occasionally.

Matt, around here the summer is when it would die back. None of the native grasses get to 12 feet, which is probably just fine.
Scott, I've never seen an elderberry spread with runners. Sounds almost as hard to do as a fig hedge. Quite contrary to its natural bent, which is upward in both cases. At least the ones I have grown.
Celeste, pomegranates make a great hedge. I've seen them, I now recall. The small leaves are visually excellent. Great idea.
Turns out I have had the fence rebuilt. Figured a hedge would be too slow to establish, and too much pruning and maintenance, for my current situation. We are entering the dry season - nothing will grow until November. I'm planting native shrubs inside the fence that might be big enough to be fine without a fence the next time the fence needs replacement, in a couple or three decades.

Hi Ellen. I grow three different varieties of elderberries on my farm. They form a fast and tall hedge from runners in short order.

Scott, you probably get rain. We don't (at least not from March through October). I've grown the caerulea and the nigra and have never seen runners. Interesting to find out what they do under different conditions.

I would like to recommend two of my favorite shrubs.  They grow well in Texas so maybe one of them will work for you.

I first saw this one used as a hedge.  I think they look like an artificial Christmas tree:

Guayacan, Soapbush, Guaiacum angustifolium - Melastomataceae

Guayacan is an unusual evergreen shrub in the Caltrop Family. It has extremely hard wood, and its branches are so short that the leaves seem to be growing from the stem.

The leaves are pinnate and have tightly clusterd groups of 4 to 8 tiny leaflets that grow in pairs. From March to April its numerous fragrant flowers bloom, each are about 1 inch wide and has 5 violet-purple or pink petals. The fruit is yellow and has 1 to 3 shiny red seeds in each.

Guayacan offers good forage for deer and excellent cover for birds and small mammals.

https://rangeplants.tamu.edu/plant/guayacan/

Leucophyllum frutescens aka

Cenizo, Purple Sage, Texas Ranger, Texas Barometer Bush, Texas Silverleaf, Texas Sage, Silverleaf

A gray shrub with leaves densely covered with stellate, silvery hairs and bright pink-lavender, bilaterally symmetrical flowers borne singly in crowded leaf axils. Typically a compact shrub, 2-5 ft. tall, Texas barometer-bush or cenizo occasionally reaches 8 ft. in height, and 4-6 ft. in width. Leaves silvery gray to greenish, soft to the touch, up to 1 1/4 inches long but mostly 1 inch or less, tapering more gradually to the base than to the rounded tip, margins smooth. Flowers violet to purple, sometimes pink, nearly bell shaped, and up to 1 inch in length and width, appearing intermittently from spring to fall. Fruit a small capsule.

https://www.wildflower.org/plants/result.php?id_plant=lefr3


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I thought the suggestion of grasses as a hedge was a great idea.  If you are considering options as low as 3 feet and up to ten there are a lot of options.   In your climate some are probably evergreen.  But I personally like the look of my feathergrass when it goes dormant in the winter. Depending on how it was maintained there might be a brief window of time each year between clearing the last seasons growth and getting height from new growth where the "hedge" would be very short.

I've been eyeing this site https://www.molokaiseedcompany.com/product/sunshine-vetiver-grass/  and considering getting some to use as hedges separating different sections of the yard. We have a good variety of native options here, but it would be much harder to keep them within bounds.  These get very tall which would give me abundant mulch for the garden at least once a year but it sounds too tall for your tastes.

https://ebcnps.org/news/adding-california-native-bunchgrasses-to-your-garden-2021-07/

This article has a great picture of your native deergrass (three to four feet +2 feet when in flower). I can just picture drift roses planted in the spaces between where the thorns would discourage dogs from squeezing between.  A clearly defined border with the gracefully arch and sway of the grass offsetting the repeating flushes of flowering roses.  The same people who bred the knockout rose are responsible for the drift roses.  I have both in my garden and they survive on absolutely zero care.

Too late to help you here, but I always like to plan minimal effort flower beds.  It's my not quite secret shame that I enjoy my ornamental plants more than the crops... unless the crops are ornamental.