List of potential cascading plants for retaining wall
Hello, I've been lurking quite a bit and slowly landscaping at my new house. I'm discovering that I really enjoy this. I don't have a lot of experience, but I've been researching till my eyes are crossed and I'm ready to tackle the retaining wall in front of my house. Lawn has been placed, with an 18" strip left bare along the wall, which faces west and gets quite a bit of sun. There's an irrigation system in place so dryness isn't really an issue. Soil is nasty clay, but I've been adding garden compost.
I've been considering:
Petrorhagia tunica saxifraga... but is it too upright? I see it described as cascading but all the photos I can find are awfully bushy. I'm concerned it might be too messy.
Veronica cascade speedwell... I like the plant as it appears in 4" pots, but I haven't been able to locate photos of it in larger quantity. I'm concerned about it being unattractive when it's not flowering. Someone here mentioned their speedwell was invasive. Would that be a problem with the cascading variety?
Phlox stolonifera... I really prefer the appearance of this plant over the p.subulata, but is it in fact cascading?
Saponaria ocymoides (soapwort)... I love this one in photos, but haven't seen it in real life. Any negatives?
I would appreciate any comments on these plants, and any other suggestions as well.
Here is a link that might be useful: