There have been discussions on Saffron Crocus (C. sativus) on both the North American Rock Garden Society forum and Scottish Rock Garden Club forum. The answers are not as black & white as might be imagined. Hint for you non-Forum users, click on any thumbnail image to enlarge it, click on any page number in a topic to move among pages. Crocus sativus discussion on NARGS http://nargs.org/smf/index.php/… Crocus sativus discussions on SRGC http://srgc.org.uk/forum/index.php/… http://srgc.org.uk/forum/index.php/… Mark McDonough Massachusetts, USA, USDA Zone 5