Parsley can be used as a green or a herb, lettuce will reseed and survive the winter, Kale can be fall seeded. Many herbs will take well to being mulched and left (thyme, sage, mints, etc). You mentioned asparagus, also sunchokes.

Hav fun!

Sorrel may be iffy in your zone, but worth a shot. How about rhubarb?
Arugula would be good--it's a reliable seeder for me.
I'd keep the chives away from the asparagus--I've learned the hard way top keep the asparagus solo.
You may want to check out this book: Perennial Vegetables: From Artichokes to Zuiki Taro, A Gardener's Guide to Over 100 Delicious and Easy to Grow Edibles.

Thanks for the replies! I will have to check out the book for sure!

The current issue of Mother Earth News has an article on perennial vegetables too. There were some things I had never heard of before in it that may be fun to experiment with.

Ground cherries will re-seed themselves, too.

Arugula and lettuce have been wonderful re-seeders for me in zone 5 (and very pretty when they go to seed as well). But parsley has only been good for one year in my experience.

I've heard that parsnips re-seed well. Didn't work for me on my first try, but am trying again this year. I've also had kale plants live for years -- I have no idea why they didn't all bolt and die, but I have a kale area that's going on 4 years now.

Sage, oregano, tyme -- definitely

Also great re-seeders: claytonia, mache, rutabagas (which are beautiful in flower--huge and yellow, and makes bees very happy)

Hurray for lazy gardening!

The problem with self-sowers is the constant expansion, and more so, weed-control is difficult. The solution is to clear an area out every few years.

BTW, rutabaga and russian kales will cross - all brassica napa.

Another brassica self seeder, if you let it bloom, is chinese cabbage. Probably all the brassicas, but as the previous poster noted you would probably get lots of crossing without some care. What about cardoons? They are a little more cold hardy than artichokes.

I would almost think that any cool season crop left to seed would self sow. That book sounds intesting for sure.

Asparagus comes to my mind, too. What about strawberries & rhubarb? You could make a pie :-)

Oooo, strawberry rhubarb pie with sweet creamcheese layer on th bottom and whipped cream on top... Good memories, good memories.

salad burnette?

Here are some more herb suggestions: Sage and thyme for me are almost an evergreen, and plain oregano comes back every year. I accidentally let one fennel go to seed last year and have 6 nice plants coming up. For greens, Swiss Chard will also reseed and looks so pretty. Yep, I love "lazy gardening", too!
Edie

In my temperate climate, rhubarb's a year-round crop.
Jerusalem artichokes aka sunchokes are hugely prolific and produce tons of biomass for compost. Be warned though, they need to be segregated from dug areas as every tiny tuber will grow.
Egyptian walking onions. Indestructable in my climate.
Shallots and garlic I missed harvesting keep coming up forever...
I've only grown salsify, but I'm going to try it's perennial cousin 'black scorzonera'.

I put in Evergreen Bunching onions, Lisbon Bunching onions, Chives, Garlic Chives, Garlic Mustard and Kale.

I will also leave a few carrots in for next year to see if they reseed in Zone 5 and Cilantro which will hopefully reseed as well.

I have had Swiss Chard survive until the next year only to die in a late frost. I might try to much a few plants this fall.

All I need to do is get some potato onions if i can find them in the fall. I missed Shallots this year and will plant a little garlic as well.

Thanks everyone for the help!

I am NOT the best resource on the topic (I'm a long-time annual veggie gardener who now lives in a perennial-friendly climate and is trying to re-learn), but thought I'd chime in on what I do grow perenially.
I inherited a garden with Jerusalem artichoke and asparagus. The J.Artichoke I kept because its rather foolproof, but I find the asparagus to be finicky, and it looks like it won't be coming back this year. I mostly added perennial herbs which most have mentioned above(like I said, still trying to learn), but I have had quite a bit of success with two plants - parsnips, which biennially go to seed and self-plant for me, and comfrey (bockings 14 sterile variety) which has become a nice perennial fixture and source of nutrient-rich green mass. I'm not sure if that would interest you or not though, as it needs to be hacked down periodically (at around 2') or it can grow quite large.
What on earth is a potato onion?

A potato onion is a mild multiplier onion that gets a 2-3" bulb and multiplies by producing small bulbs around the bigger one. You eat the big bulb and plant the smaller ones to grow. They are not cheap but they said once established you should never have to buy onions again. I am sure that can take a few years to get an established garden.

Lovage is another herb that is a perennial. Celery-like flavor, it makes a great addition to soups.

So far in my yard I have asparagus, rhubarb, lovage, thyme, lemon thyme and sage.

Where I live, all the traditional gardeners have asparagus, rhubarb, strawberries, chives & mint.

I've had cilantro reseed itself. I 've also read about sunchokes (aka Jerusalem artichokes) and have started some in a planter on the deck. Echinacea is also a perenniel.

Glad to see lovage mentioned. Great stuff & hard to find.

SOme of these are said to be invasive. I haven't had a problem yet, but I haven't been at it very long either.

I'm all for less work in the garden, but I think I'd rather dedicate my gardening space to things I really want to eat, not just ones that require the least work. Although perennial vegetables can be a good idea, I can't imagine being without my tomatoes, potatoes and other annually planted veggies.

I agree Donna. I have started a small perennial garden and right beside it is the garden for my beets, tomatoes, peppers, squash, etc.

Well, if we are going to name strawberries, why not blue berries,raspberries,black berries & a little mint for taste.

Don't forget fiddleheads!

Jerusalem Artichokes,horse radish,dandy loins, Chinese Artichokes, Poke plant & Bamboo sprouts.