website giving me the information I needed -- about 12 weeks of cold.
But then I read down farther and saw they stated that Iris reticulata and Scilla require no cold period to flower.
Wait -- what? You can just pop them in a pot like paperwhites and they'll flower? I looked for confirmation and found this fact sheet from University of Rhode Island confirming that Iris reticulata needs no cold period. Haven't been able to confirm the Scilla -- this page from the University of Wisconsian says they need 6 weeks of cold, and I'm inclined to believe them. Perhaps the first page was refering to the tropical Scilla peruviana.