Coneflowers seeded themselves.

Bottom of steps.

Opposite side

One last picture.

Irrigation?

Hand watering. Wish I had another way.

Didn't realize how dark that last picture was. Here's a lighter one.

Have you considered any of these? All are growing/thriving in full sun where I am.

Baptisia australis/false indigo
Chelone/turtlehead
Nepeta/catmint
Stokesia/Stoke's aster
Hibiscus moscheutos/hardy hibiscus
Agastache rupestris/sunset hyssop
Campanula persicifolia/bellflower
Penstemon/beardtongue
Coreopsis/tickseed
Euphorbia polychroma/Cushion spurge
Liatris spicata/gayfeather
Perovskia atriplicifolia/Russian sage
Phlox paniculata/tall garden phlox

I garden primarily to attract/sustain pollinators (bees, butterflies, hummingbirds) so the plants listed above are growing where I am for the critters' needs which may or many not mesh with folks using your pool.

Best of luck.

What is your goal for this area? All summer color? Year-round interest? Food for pollinators? Flowers for cutting? Are you OK with bees visiting flowers since it's near the pool?

What kind of maintenance are you willing to do? I imagine that you'll want to avoid anything with berries to avoid mess on your pool deck. Are you willing to have to sweep up spent flowers from the pool deck? Do you deadhead?

Between the south-facing aspect and the non-level ground, I imagine that the area is fairly dry. Gardenweed has given you a good list, though IME Chelone and tall garden Phlox may need more moisture than will be available there.

A few other plants to check out:
lavender
Caryopteris (I particularly like Sunshine Blue with golden/chartreuse foliage and late summer blue-purple flowers.) Very low maintenance in my garden.
sedums
thyme
Geranium 'Rozanne'
some of the groundcover/rockgarden saxifrages

Great drainage, reminds me of plants I like to grow that need it, and I have trouble providing. Agastaches and Salvias.

The other thought I had, is that the edge of that wall would be great for spring bloomers, with Phlox subulatas and Basket of Gold with a bulb display planted so other perennials would disguise the dying foliage.

And on the other end, in the fall, maybe some asters or Mums for fall color.

Blue Chip Juniper trailing down the tallest section of the wall is a low moisture plant. Sedum matrona has multi seasonal interest and drought tolerant. Catmint 'Walkers Low' is a very long bloomer and needs little water. Red Knockout Rose would stand out and is a low fuss plant. Its a pool area so I would concentrate on summer bloomers. Toss in an annual purple fountain grass for foliage contrast and some Licorice plant trailing on the lower wall section. Go away for a week in summer heat and nothing to worry about, All tough stuff.

Wow, I wasn't expecting so many options. Since I don't know too much, I'll have to look up a lot of the suggestions. I love the many butterfly's and the one or two hummingbirds that visit and would like to keep them around. The bees don't bother us as they tend to stay in the flowers. With this new wall the bees can't hide in it like they did in my dry stack wall we had previously, but they never seemed to bother anyone. I love having cut flowers. Too bad I'm not better at arraigning them.

I would love all season color minus winter as I can't really see too much of this area from my inside. I do have another area that I can see have have grasses and shrubs that provide some winter interest.

Gardenweed- Russian sage is one of my all time favorites and I have quite a bit of that. I like the idea of adding some coreopsis and that would be free as I have enough in the other part of my yard to split. Catmint invaded us. I love the plant, but with two plants we started with my whole yard was full. Lol. Phlox is a definite and the rest I have to look up.

Nhbabs- yes, no berries. I do try and get out and deadhead when I can. I have quite a big year and lots of garden area. Ill try and post another picture of the whole yard, but its a bit messing right now with the wall construction. I was just talking to DH about sedum. Funny thing about my yard is that I can't kill anything. Everything seems to love this yard. Mums, oh yeah, didn't think of that. Great idea. Maybe on the side that I can see from my patio doors.

Chrunchpa - we just put Russian cypress on the tallest section of the wall and may add one or two more. Is this similar to the juniper? Red knockout rose would do well also. I have one on the other side of the patio we just planted so another would be good. Purple fountain grass I'm going to look up. I love grasses.

I have plenty of garden that I am redoing in the future so what doesn't fit in one garden will fit in another.

Thanks again everyone.

Wow, I wasn't expecting so many options. Since I don't know too much, I'll have to look up a lot of the suggestions. I love the many butterfly's and the one or two hummingbirds that visit and would like to keep them around. The bees don't bother us as they tend to stay in the flowers. With this new wall the bees can't hide in it like they did in my dry stack wall we had previously, but they never seemed to bother anyone. I love having cut flowers. Too bad I'm not better at arraigning them.

I would love all season color minus winter as I can't really see too much of this area from my inside. I do have another area that I can see have have grasses and shrubs that provide some winter interest.

Gardenweed- Russian sage is one of my all time favorites and I have quite a bit of that. I like the idea of adding some coreopsis and that would be free as I have enough in the other part of my yard to split. Catmint invaded us. I love the plant, but with two plants we started with my whole yard was full. Lol. Phlox is a definite and the rest I have to look up.

Nhbabs- yes, no berries. I do try and get out and deadhead when I can. I have quite a big year and lots of garden area. Ill try and post another picture of the whole yard, but its a bit messing right now with the wall construction. I was just talking to DH about sedum. Funny thing about my yard is that I can't kill anything. Everything seems to love this yard. Mums, oh yeah, didn't think of that. Great idea. Maybe on the side that I can see from my patio doors.

Chrunchpa - we just put Russian cypress on the tallest section of the wall and may add one or two more. Is this similar to the juniper? Red knockout rose would do well also. I have one on the other side of the patio we just planted so another would be good. Purple fountain grass I'm going to look up. I love grasses.

I have plenty of garden that I am redoing in the future so what doesn't fit in one garden will fit in another.

Thanks again everyone.

Some other picture. Thanks again

Opposite side of pool

View from patio.

NatalieW - your garden is stunning already so I'm guessing it'll be garden tour-worthy before long.

Coreopsis 'Moonbeam' would have been my preference early on due to the pale yellow blooms but I've learned 'Zagreb' is much more reliable in my zone + it enlarges with each passing season so it can be divided and planted in other areas of the garden.

Russian sage is also spectacular planted with Gaura lindheimeri/wandflower.

There are plenty of perennials that meet the needs of gardeners with defined goals & objectives.

Best of luck!

Beautiful garden. Perhaps some low growing plants for the front of the border-dianthus, moss phlox(subulata),or campanula'clips'. Or low growing foliage plants like thymes or sedums that come in different colors, bright yellows,reds, and varying shades of green all which do fine with minimal water. All mentioned do well in my zone 5 sunny gardens.

Lovely yard, Natalie. Very inviting!

Dee