For those interested in this species, please see: http://desertmuseumdigitallibrary.org/public/… undulata I've heard people in the plant community here say these bulbs have been found growing as deeply as a meter. Even if they were at a two-foot depth in sand, this alone would account for expected cultivation difficulty. Unless rain is torrential and/or prolonged, it won't reach the bulb to initiate flowering which helps explain why they don't flower every year. Best flowering occurs in wet years here. That means wet winters since these flower in late spring. Same with Borrego, as Michael noted (and thanks for that info). However, if any of you would like for me to ask locals in the botanic community whether anyone has succeeded in growing these in home landscape or greenhouse situations, please contact me and I'll be happy to oblige. Pamela Pamela Slate P.O. Box 5316 Carefree AZ 85377