Is it savable? Will the stalk regrow roots and how can I save it?
The stem of the hosta is actually the part that is underground -- the rhizome. The stem you're looking at is actually the leaf stem -- a part of the leaf -- and hosta can't grow roots from their stems. But the rhizome should send up some new growth soon.
Can you divide hostas in the summer if deer ate leaves?
Here's an article with some answers for you: https://www.gardeningknowhow.com/ornamental/foliage/hosta/transplanting-hostas.htm
Something is eating holes in hosta leaves. Have tried Sevin, but didn't help.
This article has some possibilities for you to look into: https://www.gardeningknowhow.com/ornamental/foliage/hosta/hosta-problems.htm
Once hostas are done blooming, is it ok to cut the stems (with the leftover pods) off at the base, or should you leave them to wither naturally?
Yes you can cut them. You can also cut off yellow and brown leaves.
Can I store hosta in their pots in an outside enclosed, non-heated shed over the winter? Should I cut them back before they start shriveling up for the winter?
If you're keeping them in pots, they need to be in a place where they won't go below freezing, because plants in pots don't have the insulation of the ground to protect the roots. Don't cut the leaves back until they've shriveled - the rhizomes use the materials in the leaves to store up food for the next year's blooming. Hostas in your area should be perfectly adapted to overwintering in the ground (they're hardy to zone 3, even 2 some people say) if you want to use them that way. These articles might be useful: https://www.gardeningknowhow.com/ornamental/foliage/hosta/growing-hosta-plants.htm
https://www.gardeningknowhow.com/ornamental/foliage/hosta/hostas-containers.htm
https://www.gardeningknowhow.com/ornamental/foliage/hosta/transplanting-hostas.htm
Bought hostas from yard sale - woman said they had slugs - in containers, not planted yet. If I take out plants, rinse thoroughly and then plant in ground, will the slugs be gone? Thank you!
First of all, slugs do not typically remain in the pot with the plant and only come out to feed at night, so I doubt that will be a problem. It is possible that the lady mistook the insects for weevils, which have grub-like larvae. If this were the case, the following article may be helpful: https://www.gardeningknowhow.com/plant-problems/pests/insects-in-the-roots-identifying-and-controlling-root-weevil.htm
If you take them from the pots and rinse thoroughly, however, this will certainly help take care of any possible issues. And should slugs become a problem, this article will help: https://www.gardeningknowhow.com/plant-problems/pests/facts-about-slugs-and-how-to-kill-garden-slugs.htm
My Hosta should have leaves that are green in the center with white/cream edges. Instead, the edges are red/pink. What causes this and what should I do to correct it? Thanks.
The most common cause of color change in hosta is light, either too much (relative to the plant's requirements,) or too little. Have you had this variety for at least several seasons, and find it is suddenly changing? If so, you might want to consider the light where it's growing, and if you want the cream edges, see if there's a place in your garden to move the plants where the light is more like that they had in earlier seasons. This article might be helpful: https://www.gardeningknowhow.com/ornamental/foliage/hosta/transplanting-hostas.htm