Here is a series of pictures I made recording this process, on the Scottish Rock Garden Club Forum, as I have practised it. http://www.srgc.net/forum/index.php?topic=6450.0 I would not recommend planting Onco Iris in pots of pure sand. if exposed to warm sun. Possibly seedlings in a bed of course sand would be good, but I would still top 'dress' with grit. Sand has a capilliary action which can bring moisture up to the surface, and if the surface is warm and wet bacterial rot will kill oncos very quickly. Chlorine can stop the rot if applied in time. I always add some clay / loam, and for newly germinated seedlings I may even use a peat based compost with a lot of fine grit. When temperatures are right -(cool but not frozen), oncos can use quite a lot of water and do not like to dry out. There are many details of my experiences, and those of others, in the thread which this link goes to, and its successive page, as well as a link from there to a similar experiment by John Lonsdale. I suggest that Janis's (Ruksans) comments are well worth reading. It is so easy to have 'accidents' with seedlings I offer my condolences! I am not sure how removing the aril exposes the embryo.... Peter (UK) On 15 November 2014 21:23, penstemon <penstemon@q.com> wrote: > Now to work up the courage to cut them. > > > The seeds were soaked in a solution of fifty percent bleach and distilled > water for about fifteen minutes. The seeds were then thoroughly rinsed, > with distilled water, and put into salt shakers (purchased expressly for > this purpose), water changed every day, for four or five days. > Then the arils were removed using a dental pick, making sure that the > embryo was exposed. The seeds were put in freezer bags with some perlite, > and put in the crisper drawer. (Thereby decreasing my intake of fresh > vegetables.) > One of the Iris urumiensis (JJA 600.600) germinated about a month ago. I > transplanted it, and it grew. Then I had the bright idea of transplanting > it to a pot of pure sand, thinking that the sand would dry out faster, > thereby preventing rot. Then I had the even brighter idea of watering it, > since the oncos in the garden display none of the hydrophobia so often > mentioned in the literature. The sand refused to dry out (it must have been > some new miracle sand), and the leaves started browning at the tips. > So I transplanted the poor seedling again, into to my standard seed > starting mix. Today, with my usual skill, I accidentally knocked the pot > over, dislodging the root from the tiny rhizome. >