I have roughly 2500 clumps of tets, and we are talking up to 40 fans in a clump, and had maybe six that got spring sickness this year, while as I mentioned, there was none at all last year. The dips had roughly 50 out of about 400 or so. My results are nothing like yours though. The plants that seemed to get it had a crown at ground level to begin with. The side shoot fans were newer, but the crowns were beneath the surface, but are mature enough to bloom this year. It just seemed to me that what I call "spring sickness" was most likely the result of freeze damage, and while science grapples with the causes, I am going to stick with my theory if it means that I don't have much of it. There was a time when my tets did have a big problem though. I am going to try adding a layer of mulch this year to the diploids that are problematic to see if it helps. All I can do is try, right?
this photo shows just one of five "beds" taken two weeks ago, but I have deleted photos of plants with spring sickness already. This same bed is now double in size.
