I recently used some slow-release garden sulfur on a raised bed where I had planted Lilium speciosum var. rubrum and var. album. I am hoping it works fast enough to allow them to establish and grow well. I will try to get some more for my L. lankongense hybrids as well.
My garden is on the north side of Chicago about a mile away from Lake Michigan, which explains my somewhat moderated temperatures.
I know Madison well. I love the Dane County farmers market and the restaurant L'Etoile.