Salvia guaranitica is a tough customer. I've had a clump of "Black and Blue" return for several years, including after lows to -19F last winter. Full sun, mulching and location in a well-drained area help.

Out of all my supposedly tender plants (such as dwarf palmetto, Amorphophallus konjac and Mirabilis longiflora) only one croaked as a result of the harsh winter - Texas tarragon (Tagetes lucida). It wasn't a huge loss since I hadn't been able to get it to flower here.

Well since oxalis are related to some of the worst weeds on the planet IMHO, it's not surprising they are tough overall.
I too was surprised my Calla lily survived here with no special care, but it is growing in a natural wetland area and had snow cover during all the freezes (very lucky) and some surrounding vegetative cover like Scirpuses. (Scirpii? haha)
Much as cold winters are a downer, it's good to have one once in a while to stay realistic about climate, and learn about plant tolerances. I let my Euphorbia characias self-seed around the garden and one clump showed much less damage than the others...should I introduce it?

I have been meaning to try Hymenocallis so your report is encouraging. Do you remember which ones survived?

This post was edited by davidrt28 on Thu, Sep 25, 14 at 3:59

I have Ismene, Sulphur Queen hymenocallis. I'm not sure if the name is for the same plant, or if Ismene is one variety & Sulphur Queen is another. I know I have 2 varieties, they look different & bloom at different times. Which is which, I can't say. One has multiplied quite a bit & has much larger foliage, the other one returned, but has never multiplied & I think I lost on of the bulbs. Sorry I can't help more than that.

Nice, thanks for the update. Is either fragrant?

They are somewhat fragrant, but not to the extent that lilies can be.