Well, it didn't make it. Most definitely not a zone 5 plant. Mine was in very well drained sandy soil, not cut back until spring, and though we had a cold zone 6 winter, it was not a zone 5 winter. I finally pulled it yesterday.

I bought six Windwalker Royal Reds at Bluestone Perennials last year. They did very well in my garden near Pittsburgh, Pennsylvania. Only one them is coming up this month and it looks good actually. The other five didn't show much and I may not have given them enough time, but I pulled them. It will be interested to see how the one survivor does. My soil is really tight clay, sightly amended.

What is your zone? Mine definitely didn't make it.

Since neither of the parent species (S. darcyi and S. microphylla) are hardy to zone 5, it would seem unlikely that their hybrid offspring would be either. Hybrid vigor is one thing but increasing winter cold hardiness by a full two zones seems overly optimistic!! I'd rate the Windwalker series only to zone 7 although you may get a few freak survivors in a colder situation, depending on drainage and the weather.

One of my local garden centers had windwalker this spring, so I picked one up to try. It certainly is vigorous. I live in zone 5a, but I know from experience that these zone 5 labels being slapped onto some salvias and agastaches are bunk. I take cuttings of all my plants in autumn and overwinter starter plants in my window because it's unlikely anything will come back in spring. The label on my windwalker says zone 5 perennial, but there's no way it's coming back next year.

Zone 9/10. I’ve tried this one 2 years in a row in different areas and have had no drought tolerance or resistance at all. It seems that it has too much of the darcyi characteristic to abort life at any sign of heat with dry in my area.