Mr. Truncata: well to me it happens too- some gemmae produce bigger and faster growing plants and some smaller and more troublesome. I collect the gemmae manually so my guess is that the reason for this is different stage of gemmae maturity when collected. Some might not be ripe enough to produce full-speed growing healthy plant. BTW my nitidula ssp. omissa x pulchella is huge also. Most of my pygmies are bigger than for example adult burmanii or burkeana or whittakerii. They really like it on south windowsill with >35C and lots of light. Thanx for nice comments btw:-)