No not really Rick - I've been growing this plant for 15 years with no problems - I can't say this for callosum's - never been able to keep a plant for more than 5 years - so far
That's very interesting Uri.
I recently got a large multi growth lawrencianum so can't say much about keeping it versus the callosums. But I have yet to keep a BS callosum for much more than a couple of years. They grow and flower like crazy in the meantime.
I have a bunch of seedlings from a selfing I did. I'm going to try several strategies for potting mix and light levels on them.