I ordered 14 new semps mail order, found out they are arriving Saturday. We're still in the middle of winter. Plants are arriving bare root. I want them in troughs this summer, but have not even made them. How do I hold them over.

I just got some bare-root specimens from SMG, I'd guess you did too. One I planted directly in to my semp garden and for good measure put an inverfted pot over it for tonight and tomorrow night. The others I just laid the roots on some bar soil and spread some loose soil over the roots and covered them with a large plastic cloche.
I guess it depends where they're coming form and going to. I would moisten their roots and keep them protected from frosty conditions for a while, which basically means to keep them covered for the next few nights and plant them when some relatively mild weather appears.
Anyway, that's my strategy

Mine are coming from Youngs Garden Center, we've been having freezing rain for a couple of days. I hate to pot them up and then move them again to hypertufa.

I have my Youngs order ready to place, ordering early because I'm not even close to receiving plants but want to lock them in, because of the big west coast - east coast climate difference, I've been telling the vendors the date when I can first accept delivery (for me in Massachusetts, it's April). Greg, being in Kansas with lots more winter to bear, the semps will be okay planting them up and keeping indoors in the brightest window you have, they will etiolate (stretch) and not look great but the plants should adjust if you get them outside once spring arrives, acclimate them gently into the sunlight, then plant them outside.

Hi Greg,
You can safely pot them up and place in your garage until your weather warms up.
@goldfinch4 Chris has done this many times with wonderful success. Maybe she can give you more information on what to do.

Hi Greg - whenever I see your name I think "wait I didn't post that?? I'm also a GregC haha"
I've kept semps open in their shipped bags in a garage for more than I month...it isn't ideal but it is better than putting them into freezing temps when they are shipping from a warmer climate...Good luck!

Thanks for the tag Lynn.

Greg, I'm in zone 4 here. That's happened to me before too. I usually just put my potting mix in a big aluminum pan (with holes punched in the bottom) and pot them up until ready to plant. Nothing fancy, but it'll help them survive until you're ready to plant them in your troughs. I keep them in a unattached, unheated garage, by a window if possible. If you're still getting freezing temps I'd just moisten the soil a bit before planting - keep them on the dry side.

Thank you Chris.

Thank you all.. I felt like a criminal hunched over the table potting away in a dimly lit garage. I'll post a list of cultivars later.

Aw, don't feel like that Greg. It's what we all find that we need to do to keep these plants that we love alive, healthy and beautiful.

Okay here's the haul:
Sempervivum globiferum subsp. hirtum 'from Bulgaria'
Fire Dragon
Pacific Magic Night
Larissa
Utopian
Zorba
Purple Passion
Blue Boy
Twilight Blues
Piliferum
Soothsayer
Patent Leather Shoes
Big Blue
Lilac Time
Santino

Nice list Greg. And we would love to see a photo of your new planting in it's temporary home.

I lucked out at Home Depot and found plant starter trays. Each tray has 18, three inch pots. Some of the plants that arrived had to be divided into 2 pots. I bought a second to have on hand for future emergencies.

Great find Greg. Photos, pleeeease. I love to see the photos.

Lots of pretty semps Greg! Thanks for the photos.

Yes, thank you, some of us love to live vicariously through other people's fun.

Oh Greg, those are wonderful. Sighhh, it makes me want to get new semps. How sweet your new babies are. Thank you so much for the photos.

Really excited abot making a "blue" and "lavender" troughs this summer.