1-What do you mean you are "staging" them?  Are they in containers?  B&B?  Bareroot?  

2-Now is actually a great time to plant trees, but you will need to keep them watered if there's dry weather at all, like what we had the past week.   (Assuming that your part of Kentucky got what we got--week before last it rained all week, then last week it was very dry.  I would have been watering by the end of the week, as an example.

It is my opinion that you are more likely to keep them alive planted in the ground, than if they are NOT planted in the ground.

If you want to try to hold them above ground, then yes, you need to heel them in with deep mulch.  I would probably dig a ditch and actually plant them in it, (right in the container or ball) then mulch heavily, then plan to dig and plant BEFORE the sap begins to rise in the spring.   Definitely before they break bud.

In that case you need to either dig AFTER the leaves have fallen off of them (probably now or within the next two weeks or so) and replant them, or leave them and mulch them for winter.

But the longer you leave them there, the more their roots will grow (roots grow during the winter) and the more damage you will do when you dig and transplant them.  

Just like kids heal quicker and easier when their bones break, your young trees recover from the transplant shock more easily and quickly when they are young.

Ask if you're not sure about good transplanting procedures.  They are not intuitive and people don't automatically know them.

ETA:  Timing is more critical in the spring.  You have to be ON IT to get them dug after the ground thaws, but before the buds swell and break.  

If those were my trees, and I had time, I'd transplant them this fall.  

Dig your holes BIGGER than you think you need them, and make sure you bust up teh dirt on the sides.  The clay we have in the soil in Kentucky will glaze over the sides of the holes you dig, and will make almost a "clay pot" effect, which will cause the tree roots to grow in a tight circle and never expand into the surrounding soil.

Busting up the sides of the planting hole with your shovel, so it's not smooth at all, will prevent this.

When I say dig your hole big, I mean WAY bigger than you think it needs to be.  

Mulch it for the winter.  Don't pile the mulch up high around teh trunk, but make it pretty thick.

Depending on the size of the trunk of the sapling, I might surround it with some kind of protective shield...this will help the deer and other animals not nibble on it to the point of killing it.

BTW:  When you say "redwoods" do you mean the kind of redwoods that grow near the California coast?

Dawn Redwoods can get relatively large.  And they're wide trees, so give them plenty of room wherever you plant them so they can become the really awesome trees they're meant to be.  

If the trees are planted properly, then no, I would not try to protect them from frost.

Consider that idea a little more deeply and I think it will make sense to you.

These trees are hardy in Kentucky.  In their real life, without you interfering, they will lose their leaves and go dormant in fall, live through the winter (as long as it's a normal winter) and leaf out again in spring.

If you coddle the tree, you reduce the trees ability to adapt to really cold temperatures.  You can't save the tree from extreme cold--and it WILL get extremely cold at least a few days a year here.    I don't think you plan to keep it warm every night and uncover it every morning all the way through the winter, right?  And if you do that,  what happens next winter?

Letting the tree go through its natural cycle (once again as long as it's planted properly and mulched) is the best thing for the tree.

MIGHT you lose the tree?

Yes.  You might.

But you might lose the tree no matter what you do.

A tree hardy in zone 6 will survive in zone 6 unless something else is wrong.

The ONE exception I can think of is if you dug a tree in Georgia this summer and brought it here.  That tree probably won't survive anyway.  It might, but odds are against it.  It does not have the genetic background to be hardy here.

The best thing you can do for them is to get them in their final growing place as quickly as possible, and do a good job planting them.  Make sure they're not where the roots will be wet without draining.  Make sure they don't get planted and then have no water for the next four weeks.  

With regard to hole size...I need to know what the trees are in now.  Are they in containers?  B&B?  Bare root?  Or what?  If they're in containers, what size?  If they're B&B, how big is the root ball?   If they're bare root, those roots do NOT need to get bitten by frost.  But I'm assuming you have them somewhat underground.

Go to Gardenweb and look up tree planting advice.   "Best way to plant a tree" or something.   You'll get good advice.

Also, KNOW your tree.  Spend an evening reading about what kind of planting site is needed for the kind of trees you want to plant.

@nisfro none of this is bad advice.

Be aware that after the first season, I would take the tree stakes down, as the wind moving the baby tree will encourage it to develop a stronger root system BEFORE it is big enough for the wind to affect it even worse.

A big hole is better.  

Where I am (South central KY a little west of the hilly area) we have a lot of silt mixed with the clay, so I don't always do this, but if you have heavy clay, I would mix in some potting mix (NOT POTTING SOIL--POTTING MIX) that's basically peat moss,  in the hole, stir it up with the loose dirt you've dug before you put in the baby tree, to give the roots a little looser mix to grow through at first.  Helps it along a little.

ALSO...one of the most important things about planting new trees is not getting them too deep.  Since they're in the ground (I'm assuming OUT Of a container or b&b at this point) you don't have a way to know the depth that they were originally planted  in the ground, container or whatever.  The ideal way is to keep them at exactly that level when you plant the tree, then mulch around them a little.  With a baby tree I will pile the mulch up around the outside of the "hole circle" but I will not pile it up around the trunk itself.  Just keep it at soil level plus an inch or two at most, around the trunk of the sapling.  The mulch is to help insulate the ROOTS, not the trunk.

If this is confusing, say so and I'll say more.