Ooh JC that really does sound amazing!! Lots of room for semps!! (and other things!) Bev is a purist and only likes semps with semps, but myself I love to mix hardy sedum in with semps, and they look pretty together!! Although for the beds I began keeping them separate, since the sedum can take over!
Honestly I think semps will grow pretty readily in a garden environment, because of the availability of nutrients. I'm pretty sure most people on here only lightly fertilize, but I think many nurseries fertilize and that's partly why they have larger sized semps. (but if they get too much there is a strong chance they'll bloom!) Here in the Pacific Northwest, Seattle and surrounding areas, the main thing we have to worry about is dampness, so having well drained soil is really important!! Its meant though that I sometimes have to water, even succulents if its been a couple of weeks without rain.
Mostly though I've noticed the opposite of what you're talking about wanting to do...which is that I have amazing hens, and its not putting out any chicks!!!
I also think that a single large semp isn't as effective as a mixing of different sizes as they naturalize in the beds!! Its such a lovely site to see clumps!
