It's biennial so if you want to save the seed you'll need to keep it alive two seasons.
If not, I would't bother. Way easier to start again than muck about protecting it.
As for the roots, in a word, no. They're fleshy, but not tap-rooted, and not tasty. No use for cooking.
I hack all my large plants off low, leaving the roots in situ to decompose and provede aeration channels.
I don't dig my garden, so that method won't work if you till!

In Pennsylvania, it's kind of "iffy" whether or not chard will survive. It survives here on in the mildest winters. Mulching doesn't actually help much, IMO, and may be harmful even, because not only does the cold do it in, but it's really prone to rotting from the moisture trapped in the mulch. It probably WOULD work if you wanted to put some kind of a cloche/coldframe/low tunnel over it and use a really dry mulch, like straw or pine needles, and keep it dry with the structure.

If it does overwinter, you will find it grows a few useful leaves, but pretty soon will bolt. Overall, as said above, unless it's for seed production, not really worth it.

I over wintered a chard last year It bolted as soon as it started growing in the spring. It was fun to see but a waste of time and space. They get big you know. About a 4' tall pyramid shaped monster. Now in the south people have grown them year round. I recall seeing pictures of 3 year old chard and it looked like a palm tree from the harvesting.

Curt

Thanks for the info. Pretty sure I'm just gonna hack it all down and freeze it. It would be kinda cool to see how big they would get, but I'm in it for mostly good edible green, so I'll pass on trying to overwinter the roots. Makes a lot of sense that dampness in the mulch would lead to rot and other nasties.

I read somewhere that Chard is better than any other vegetable for your trace elements, even Spinach.

I always let one or two good plants bolt because they self seed. I only sow chard every 5 years or so to get some new blood in. Otherwise it's all self seeded. So I would not hack all of it down but wait and see if it will set seed.

I get self-seeded chard too (and several pounds of chard seed). Some of my red chard that bolted last summer has gone back to vegetative growth for the fall, the tall stems laid down and are producing heads of leaves every few inches, if they keep it up all winter I won't have to sow more.

Chard isn't the tastiest green, but if you pick a red or gold variety it will at the very least be the handsomest plant in your veggie patch.

How do you "keep" chard?

I'm not sure how to "keep" chard. I "use" chard in many things! Mostly soups!
I'll make a 15 bean soup, or minestroni, chicken vege, beef vege, potato leek...............cut the ribs off, chop the chard pretty small, and add to all your soups/stews etc!
I also saute some onion/garlic/tomato, all chopped up and add chard til wilted. Yummy!

Just stumbled across the notion of putting chard in soup. I made a big batch of stock w/ the turkey bones and was pondering what to put in the bit I wasn't planning to freeze. Chard and carrots are the only things left in the garden that can pass for soup fodder. Yummy is right.
BeeMan: I very good friend and health food nut has told me as well that chard does, in fact, contain a higher concentration of trace elements than any other green he knows of. Yet another plus.

I "keep" chard by blanching it and freezing it. It's only good for use in soups and stews after freezing, but it's a great way to preserve it for those of us in the north who love to eat chard year round.

The leaves of Gilfeather turnip taste at least as good or better than chard and at the end you can eat the huge bulb at the bottom. That is sort of like eating the root.

Gilfeather turnip is really a rutabaga and is the only rutabaga I have ever grown. so I can not say about other rutabaga but all rutabaga have a reputation for good taste of the leaves.

I also grew a lot of chard but I think the rutabaga is much better. although they are different and I will continue to grow both.

I once over wintered some chard. Waste of time. In the spring I did not get any leaves to eat. They all went immediately to seed. And the seeds take all year to form so they take up too much space. better to buy the seeds. 2 years of garden space is worth much more than the seeds.

Anyway, You might consider rutabaga as a substitute for chard and get much more for the growing. But you should get an earlier harvest of leaves from the chard. Because I want the bulb to grow big, I do not harvest the rutabaga leaves until the fall. Where I harvest chard all summer. that is the big difference.

"And the seeds take all year to form so they take up too much space. better to buy the seeds. 2 years of garden space is worth much more than the seeds." A lot must depend on your climate. Mine is relatively mild and moist with no summer heat. I can harvest leaves pretty much all year round - certainly February to December and then starting again the following February for a few more months - so they are not a waste of space. And I only keep one or two plants for seed. In fact I don't even need to keep them until the bitter end. They go on the compost heap and the seeds come up when I spread the compost.

The thing is it grows itself and requires no effort at all from me whereas I find rutabagas much harder to get to a good size

When I lived in San Diego, I had Swiss Chard plants several years old. As I harvested the leaves, the plants would form "trunks"; when they got a foot high or so, I chopped them off at the ground, and thinned until only the strongest shoot was left. This took persistence, since the stump continued to make large numbers of new shoots.

I've only had a few sickly plants survive my Wisconsin winters. Mulch didn't help, not only for the reasons given by Denninmi, but because bugs & snails under the mulch had the chard as their only living food source.

Since chard is biennial, that makes it difficult for me to save seed... but I might have found a trick. I made a late planting in 2008, and a few of those seeds overwintered & sprouted in 2009. Only one survived my Spring tilling, and it bolted in early Summer. It appears that winter sowing might force chard to bolt in the first year. Haven't tested that theory yet, but as much as I love chard, it would be great to save my own seed.

Personally, I love the stuff. I recommend it as one of the best vegetables - and the best green - for small spaces, since you get a lot over the season from a small area.

The wife uses chard as the green in a mung bean soup, and I like it in spinach lasagna... but mostly, we just eat it with butter & salt.

I freeze large quantities for the Winter from 20-30 feet of row (if I can keep the birds out of it). This is a lot easier than spinach, since chard doesn't boil down to nothing, or get slimy. Because of the thick stalks, it needs a little more blanching time than most greens. I chop up some of the stems with the leaves, and blanch for 5 minutes.

Any frozen green is vulnerable to freezer burn if exposed to air, which might be the reason Mrswaz says it is only good for soup? If frozen completely covered in water, the chard will retain much of its quality through the winter. Freezer bags are good for this, you can squeeze out any air bubbles before sealing.

I usually freeze mine in plastic freezer containers (covered in water) to form a solid block. If I summon up the motivation to vacuum seal it after freezing, the chard will be good as a vegetable for at least a year.

Zeedman, thank you for the tip about freezing covered in water! I've just frozen chard like I do brussels sprouts. Blanch, pat dry, and pack in a freezer bag.

I will try packing it in water next year.

I know this is an old post but I have something to add regarding overwintering chard for seed. Last year I planted Erbette chard seed apparently too late as it did not come up. I assumed my seed was bad as I had had it several years already. To my surprise it came up this spring. I guess it was too hot when I planted it last year.

Anyway, those chard are now bolting and going to seed. so it is my guess that if you winter sow it and it can come up on it's own, which is really early, then you won't have to try to protect it during the winter. (unless of course Erbette is not biennial)