Tabby, I like to take a single young rosette and give it is own pot to see what it can do. I learned to do this from my experience with S. arach. 'Linde'. I grew it as a clump for years, and never saw the plants get past 1". It's very well behaved and makes a nice flat clump as it spreads, but the plants don't get big. I transplanted a few to some small pots, to have some to trade a few years ago. Much to my surprise the transplanted ones grew to 2" or more.
I've come to believe that the plants communicate to each other, likely chemically, in such a way as to say that they have neighbors. The message is that you are in a community, so don't get too big. Or we are dying here, so flower and set seed, etc. When the messages are not present, the plants can use all the resources and grow to full size, set more offsets and flower more often. Unfortunately, with all the hybrids floating around, some don't communicate within their type as well as they should. For example, I had a colony of 'Commander Hay' all decide to bloom at the same time. That included the parent rosette and all her offsets, all at the same time. I thought I had lost that variety, but later found a second pot of them at my parents house that I hadn't remembered.
That adaptability makes for interesting observations. For example, I have two versions of 'Hookeri'. One was purchased from Edelweiss and the other from North Hills. The names were slightly different, one "x barbulatum 'Hookeri'" and the other "barbulatum x 'Hookeri'". I felt at the time that these might be different, in that the ones from Edelwiess were in a larger clump and small, never more than 1". The other from North Hills looked greener and was larger, nearly 2". I've had these for several years and keep them separate, but have come to believe they might be the same plant, just looking somewhat different due to the North Hills ones not being as densely situated as the 'Edelweiss' ones. I've tried to get more information, but have never been able to find out much about either.
The question is in interpretation of the name.
"Barbulatum" was the name attached to a hybrid of two smaller Sempervivum species. At one point, nomenclature rules said that you could do this, but you were supposed to put an "x" in front of the name to denote its hybrid nature, so properly this hybrid should appear as: "x barbulatum". Then a variety of this could be: "x barbulatum 'Hookeri'".
If you then crossed it back to the original "x babulatum", you would end up with "(x barbulatum) x (x barbulatum 'Hookeri')" as the "x" can also be used to indicate a cross between two named varieties or species.
Now all it takes would be for someone who did not know the rules to just drop the x's from in front of barbulatum, (happens all the time with names like this), and be a little less formal about the barbulatum and you would end up with the other name: "barbulatum x 'Hookeri'.
So, I do not know for sure if these are different, or if these are the same, but just called by different names. I do propagate the original names, just in case they are different, and just try to relax and enjoy them.
(sorry about the long post and hope I didn't make it too confusing)
Not confusing at all Twit. Very interesting, in fact!
