Australian wrote:If you have access to older issues of the MSG Bulletin, there is an article by Piccione who explains why Lithops seedling can shrink and vanish. It has happened to me several times.
Thanks. I know, I have sown dozens of times not only Lithops but also many other mesembs. In this case no doubt that the problem was the mix; (the few) surviving plants are minutiarized versions of what they should be, and the other batch (pictures shown at the beginning of the post) is having the same care and conditions, except for the mix, and is growing healthy and strong.