It's interesting because I saw some native sedums grow on random roofs with barely anything more than dust, the seeds end up there due to wind as these are mostly abandon places that I have seen.
They seem to be doing fine with lots of ton of sun barely anything else but dust and concrete.
For example there is a bridge where some sedum ssp. simply colonized the entire sides of the bridge, barely anything more than dust and concrete sitting all day in the sun. Unfortunately the cleaning company considered this was a weed and cleaned them off the bridge, luckily some tiny places survived and less than a year 10% of the original spread is back just with some tiny places surviving this "cleaning" . But due to lack of actual substrate now as it was cleaned I am sure they will need a lot of years to get back and if they "clean" the sides of the bridge again, it's never going to get back.
But these are actually Sedums not Phedimus like in your picture, yours e can get pretty big with quite succulent leaves. I am not sure if Phedimus can take such harsh conditions like I was mentioning above.
