The only kind of sand you have to avoid in a seed mix is very silty, fine-grained sand such as comes from low down on a river. (Of course, you would not use beach sand either.) "Builder's sand" or "concrete sand" should do. If you feel that it has too many fines, put it in a fine sieve and run water through it, or just put it in a large container and run a hose hard into it for awhile until the fines flow out with the water. I grow a number of bulbs from western South America and just plant them in my ordinary seed sowing mix, which is about equal parts of coarse river sand (easily obtained here), ground pumice, and peat. I almost never make a special seed sowing soil for a particular plant, except very fine seeds and Meconopsis. Jane McGary Northwestern Oregon, USA At 04:57 PM 8/18/2008 -0400, you wrote: >I am propagating my own SA bulb seeds this fall. Could someone suggest >the grade or particle size that has worked the best for them? I am >having trouble finding "river sand" and the industrial sand comes in >different sizes.