Thanks for the nice pic nmgirl.

I'm used to seeing Agave parryi in the snow, but not a big beautiful americana!

Based on cold spells like we've just had, how hardy would you say that agave is?

They should be good to at least 10, some say to 0. The one in the photo is next to a south wall and has a rock wall to the east of it about 6-8 feet away. It was floppy but pulled out of it after all the snow and cold last winter but we didn't have the extreme cold we've had the last few days. I hope it survives.

My hopes are in vain, it looks like we're going to lose this agave.The wall just wasn't enough protection. Almost all the leaves have collapsed and I'm not sure the core survived, actually I'm fairly certain it hasn't. It's getting warm enough in the p.m. that the thing is starting to ferment. It's not quite like being downwind of a distillery but the aroma is distinctly...alcohol.
I have some pups of this agave planted elsewhere and so far they appear to have made it through. Wait and see.

Did the pups survive because they were protected by the snow?

The snow I banked up over my cactus/succulent beds seemed to have provided great protection during the brutal -23 low at my house.

I expected my parrys and havards agaves and most of my various prickly pears and chollas would be fine, which they appear to be, but I was pleasantly surprised by how well the following seem to have come through (these are mostly zone 8 plants after all):
Yucca whipplei
Ferocactus wislizenii
Echinocereus stramineus and E. engelmannii

Unfortunately, my desert agave (A. deserti) from Southern California, as well as a small Santa Rita prickly pear succombed to the cold. I'm not sure about all my woody plants, but I'm optimistic since the twigs show green under the bark.

Good luck with the rest of your agaves.