Shawnie, here's what we covered

Line the wall, add two citrus trees

This wall is a great candidate for a full hedge line, any of the four below will work well here, and they all pair nicely together if you want to mix textures rather than run just one. Space 5-gallon shrubs about 4 to 5 ft apart so they grow together into a solid screen within a year or two rather than leaving gaps.

Along with the hedge, I'd add two citrus trees in this stretch. Give each about 8 ft of space from the wall and from each other so the canopies have room to fill out without crowding. Fall (October through early December) or early spring are the safest windows to plant citrus here, it lets the roots establish before either a hard cold snap or the summer heat hits. I get my citrus from Greenfield Citrus Nursery, they field-grow their trees in Arizona soil so they transition into your yard a lot better than trees grown elsewhere and shipped in.

Moving them from pots into the ground

Since these are already growing in pots, the goal when you transplant is to disturb the roots as little as possible, passion fruit doesn't like having its root system messed with. Dig the hole the same depth as the pot and only a bit wider, then slide the whole root ball out in one piece rather than shaking soil off it. If the roots are circling tightly at the bottom, gently tease apart just the outer edge, but leave the core of the root ball intact. Set it in at the same soil level it was at in the pot, not deeper, and backfill with native soil.

Build or set the trellis in place before you plant, or right after while the root ball is undisturbed, rather than working a trellis in around an already-settled plant later. A simple wood frame or a section of cattle panel works fine, it doesn't need to be anything fancy, just something sturdy enough for the vine to climb as it takes off. Water deeply right after planting and keep the soil consistently moist for the first few weeks while it re-establishes.

Vegetables with companion flowers to keep pests down

I'd plant vegetables here mixed with some companion flowers, marigolds and similar are classic for this, they help repel a lot of common garden pests while also filling the bed in with color.

You don't need to dig out or remove what's currently in there, just top it with a fresh layer from Arizona Worm Farm. Working that in over the existing soil builds the biology back up without the extra labor of a full bed replacement. For what to actually plant and when, my Maricopa County planting guide breaks down the timing month by month for our climate.

Cover it with a hedge

Same group of shrubs as the side yard wall works well here too. Space them 4 to 5 ft apart for a full hedge line, or mix two or three together for more visual variety along the run. All four are full sun plants, and once they're through their first summer, they'll be able to live off the grass sprinklers alone, you likely won't need a separate drip line for them. Just plan on giving them a deep soak every few weeks during the height of summer on top of that first year.

Pull the curbing, cover the wall, add a shade tree

I'd pull this curbing out, it's boxing the bed in more than it needs to be, and use one of the climbing options below to green up the wall instead of leaving it bare block. I'd skip Creeping Fig here specifically, this spot gets more sun than it likes. Once that's in motion, this is also a good spot for a larger shade tree, any of the four below will give real canopy coverage here.

Desert Willow, kept to 10-15 ft

Desert Willow again here, it's easy to keep pruned to that 10 to 15 ft range you're looking for while still getting some real afternoon shade onto the house. It's deciduous, so it'll go bare for a couple months in winter, but you get a long bloom season from spring through fall to make up for it, and it barely needs supplemental water once it's a year or two in the ground.

Color that can handle the afternoon exposure here

This bed is actually north-facing, but the wall's short enough that it still catches real afternoon sun, so I'm treating it more like a sun bed than a shade one. Ruellia is my desert-adapted pick here, it stays low, tough, and doesn't ask for much once it's in. Hibiscus and Canna Lily bring in bigger, more tropical-looking color if you want that contrast, both will need more regular water than the Ruellia to keep blooming through summer. I'd also pull the rock out of this bed and switch it to mulch, it'll hold moisture a lot better for whichever of these you plant.

Replace the shrub, and let's fill this area in more

Whatever's struggling here just isn't suited to the dappled light under the Palo Verde canopy. Beyond just swapping that one shrub out, I'd use this as a chance to fill the area in a bit more with a mix of these, all of them handle the filtered light here and bring real color and texture into a spot that's tough to plant.