I have had an old 'September Sun' hosta for many years, which is always very late to emerge, but I thought that was maybe a function of the pretty heavy shade it is in. I planted a second 'September Sun' last year (in a different spot), along with all of the other new hosta, and that one at least shows signs of emerging (a little bud or ramet or whatever you call them is above the soil surface), but there are still those three that don't show any signs of life.
I hadn't realized that it might be too hot here for hostas, given that I have grown 'September Sun'. Last winter did seem to be a little warmer than several of the preceding winters; while I had some frost damage on some plants, it wasn't as severe, and I didn't outright lose anything.
The irrigation system is a "smart" system so it does moderate length of irrigation based on temperature, as well as on detecting rainfall, so it doesn't water at its maximum programmed time during the winter, even if it is "dry". Hopefully that did not cause a problem.
Thank you all for your encouragement and replies.
