Overwintering bare root trees

CrankyYankee

In the summer I donated to The Arbor Day Foundation and was promised 12 bare-root trees and shrubs to be delivered when planting was appropriate.  On November 30 I was alerted they were ready for shipping, but they've only just been sent out today. The trees are supposed to arrive next week, which is problematic for two reasons.  One, the ground is frozen solid and there's no way to even heel them in, and two, we're looking at over a foot of snow with the storm tomorrow.  Per the website, they should all be in a dormant state, but I'm not sure what to do with them when they arrive.  At this point, I won't be able to plant them until probably late April or early May, when the frost is well and truly out of the ground.   Should I keep them in a cool area, wrapped, and hope for the best?  Or should I pot them up?  Leaving them in an unheated shed would mean they'd be exposed to well below zero F conditions and I'm not sure how well small trees can survive like that - I'm pretty new to trees and shrubs, honestly!  My garage is heated to about 45F during the winter, so I don't want to 'wake them up' if possible.  Any suggestions?

punkdoc

I think you need to pot them up, otherwise I don't think they will survive. If you keep them reasonably sheltered they should survive, if they are hardy trees.

Nollie

I agree, they won’t survive that long and need potting up. Even if you kept the roots moist (essential to keep them alive) you would probably only get away with a month at best. Once potted, water and let the pots drain well then wrap the whole pots in several layers of bubblewrap or similar and keep them in your unheated shed. You might get away with uninsulated pots in the garage but it does really depend on the trees as to what temperatures will wake them up.

CrankyYankee

Thank you both - potting them up is what I'll do.  There should be 5 evergreens, 5 deciduous trees, and 2 hydrangeas.  I do have some fleece and tarps that I can wrap around them to keep them from freezing solid, but the other concern is the mice and squirrels in the shed.  I might just have to invest in some hardware cloth to wrap around them to prevent rodents from chewing them.

Fairygirl

I agree too. If you don't have suitable pots, you could use poly bags with compost or similar, if you have it. Tuck them among other shrubs. That's often better than a building, but it depends on just how harsh your conditions are likely to be over the next few weeks. I don't think that's too bad for the garage temps though - so that might work perfectly well. 
It also depends on the trees/shrubs themselves, as already said. Can you give us an idea as to what they are?

CrankyYankee

@Fairygirl I believe there are 5 Norway Spruce, 2 pee-gee hydrangea, an Eastern Redbud, a white flowering dogwood, and a few crabapples.  I would assume the spruce are the most hardy.

Fairygirl

They'll certainly be fine. I'd have thought the crab apples and the dogwood will also be pretty tough. I presume that's a paniculata hydrangea - grandiflora? They're pretty tough too, so should hopefully be ok. 
I'm not familiar with eastern redbud, so I'd need to look that up. 

It seems the hydrangea is suitable for zones 4 to 8. I don't know how that translates.

CrankyYankee

Excellent - I'll pot them up and put them in the shed.  Thank you, all!

Fairygirl

Ah  - the redbud is Cercis canadensis. I think that might need some extra protection if you have temps consistently in the minus ten to twenty teens [centigrade] or similar. 

thevictorian

I think the size of the trees is also important. The smaller they are the more likely they are to suffer in the cold. If they are bigger then they are generally hardier and won't need so much protection. Our local garden centre sells bare root tree and shrubs and they are healed in with barely any soil coverage for protection and they do fine. It's stopping the drying out of the roots that is important.