I'm sure a lot of the things mentioned factor into long term success and growth of thriving plants. The problem that I think most of us face is the incredibly rapid demise of apparently healthy bulbs. I think this can only be ascribed to something catastrophic like rapid rotting. J. John T Lonsdale PhD 407 Edgewood Drive, Exton, Pennsylvania 19341, USA Home: 610 594 9232 Cell: 484 678 9856 Fax: 801 327 1266 Visit "Edgewood" - The Lonsdale Garden at http://www.edgewoodgardens.net/ USDA Zone 6b