The book Ornamental Geophytes: From Basic Science to Sustainable Production edited by Kamenetsky Hiroshi Okubo lists temperatures for bud formation, pre growth chilling, shoot initiation in corms such as Gladiolus cultivars and species, temperature ranges for various Lilly cultivars including with the use of shade cloths. Temperatures less than 17 C aparently act as chilling for certain 'dutch' Iris for example. A google search also found another book Physiology and Storage of Bulbs: Concepts and Nature of Dormancy in Bulbs -Springer which deals with some of the chemistry involved too. Congratulations to Gastil on her experiment, I feel a parallel experiment using shade cloth and water for November, December and January might be very interesting and show many more species to be growable in her climate- without lifting in summer. Peter (UK) On Wed, Nov 20, 2013 at 7:51 PM, Alberto Castillo <ezeizabotgard@hotmail.com > wrote: > The Dutch bulb industry is based on experiments like Gastil's. Of course > the info will not be made public as it implies commercial success. It is > the reason why they can grow in cold barren Holland hundreds and hundreds > of different bulb types unfailingly. > > Gastil, you can cool your summer soil temperatures by putting a shadecloth > cover and it will do wonders. > >