Regarding how various western North American "bulbs" grow down and sideways in the soil, it should be noted that Calochortus have true bulbs, while the other genus under discussion, Dichelostemma (Themidaceae, a split from Alliaceae), has corms. True bulbs descend, I believe, thanks to contractile roots; you can see these when you lift the bulbs. The contractile roots will be withered at that time and look like wrinkled tubes. It seems to me that I've seen contractile roots on corms too, but I can't recall just which genera. Some bulbous and some cormous plants also form offsets on annually produced stolons, which would explain the situation one correspondent noticed. Stoloniferous offsetting can be uncommon in a genus; for instance, there are a few Crocus species that do it, and I can think of one Fritillaria (F. pontica) that does. In Erythronium, the eastern American species are stoloniferous, but the western ones are not, as far as I know. One reward of growing bulbs in pots is that you get to observe what goes on underground closely, but I'm happy to have left most of the repotting behind, as making up the soil mix each summer was a huge task. Another way that Calochortus increase is by stem bulbils, which form in the axils of the leaves. If the bulb is at sufficient depth, these bulbils form below the soil surface and add another strategy for survival. When you're cleaning up your Calochortus, you should always check along the dry stem for bulbils, which can be detached for planting and will produce flowering plants a year or two sooner than seeds. Dichelostemma capitatum, the species mentioned in a previous post, does make detached offsets, but D. ida-maia, the popular "firecracker brodiaea," has a lot of small offsets clustered around the parent corm. Both of them self-sow freely, as do some other themids. The production of numerous offsets in the western American themids is probably an adaptation to predation by burrowers such as gophers and diggers such as bears and humans; the tiny offsets are likely to be missed by the hungry mammals. This characteristic also makes them good for nursery production and subsequent mass planting in gardens, where their long-lasting, colorful flowers are much appreciated at the end of the "bulb" flowering season. They're especially well adapted to planting in rough grass. I recently put some dozens of Brodiaea californica in a patch of seasonal fine-textured grass on a high bank in my new garden. I had raised this large, showy species from seed in a mesh basket kept plunged in sand for a couple of years. Dichelostemma capitatum went into a bioswale or "rain garden" in the new garden, as I've seen it in vernally wet meadows. It's a lovely rich lavender color accented by dark stems. Other themids in the garden here add early summer color in a bed with a lot of colchicums, whose foliage will be up when the themids are in flower. I have admired these plants ever since childhood, when Triteleia laxa was my favorite meadow wildflower in California. Telos Rare Bulbs offers some of the less common species, and a few kinds can be found in mass-market bulb catalogs. They are very easy to raise from seed and flower mostly at three years. I suppose if you find your bulbs migrating to the sides of pots, the roots may have gone that way seeking extra moisture, and pulled the bulbs after them by contracting. If you use a soil mix with a lot of peat or similar organic component, it tends to draw away from the pot as it dries, and then overhead water will run down the sides instead of penetrating the soil evenly. That's one reason I prefer a mix that is predominantly coarse sharp sand, even though it makes the pots quite heavy. Jane McGary Portland, Oregon, USA