I really (really) think that your lack of success is attributed wholly to the
severity of your winters in NJ. To wit:
I grow D. filiformis filiformis and D. filiformis tracyi side-by-side
outdoors in Northern Virginia, therefore, both receive virtually identical
culture. In the winter, both of mine go into my unheated garage ('cause I'm
too much of a worrier to leave anything outdoors) with a relatively constant
40 degree f. temperature. D. filiformis tracyi hibernacula in my experience
(and witnessed in the wild (N. Florida in early February) are MUCH larger
though in other respects virtually identical to D. filiformis filiformis
hibernacula ... perhaps slightly more hirsute.
Perhaps yours are so dry/woody and small because the winter wind is
dessicating them? Perhaps you should try it in a plastic bag in the fridge
for the winter this time, as a test. As I've said, if the experimentation
doesn't work out, I've got the plant in spades, and can off you a replacement
winter bud.
(and NO, this is NOT a blanket invitation for requests for same. I have a
lovely large clump that I'd like to keep for now, but would sacrifice some of
its aesthetics for Dave in the name of science and public knowledge <grin>)
Jay Lechtman
L235@aol.com