A aloe plant??? LOL!!! Just kidding!!!
What abou installing some sort of irrigation so you just have to turn the water on to water them when they get too dry? Plants dont need to be watered every day, usually only when the soil is pretty dry, and if you amend the soil good enough it should hold some moisture in.
As for hardy plants, my cabbage is low-maintenance. Peas are good, along with anything that is given time to grow deep healthy roots. -cass

Corn. Once it gets established, it's pretty low maintenance, as it outgrows most weeds.

I second peas. I put my in and then do nothing(maybe a little fertilizer)until I harvest.Lettuce is another easy one. Actually a lot of things are easy once they are established.

I'm thinking sweet potatoes, but I don't know if you can grow 'em in Canada! Well, if you grew them for the vine tips instead of the tubers you probably could. I like them sauteed or stir fried! Also, what about beans? I see fields of soy beans go pretty untended on the eastern shore a lot. And unless I get a bad spider mite infestation, my beans don't ever really seem to need anything from me until harvest time. Well, at that point they need more frequent picking than once a week. Actually, I know nothing about your growing conditions- is there enough rain or is it cool enough that watering doesn't enter into this once a week equation?

Cheers!

Sunni

I can't think of a crop, direct-seeded at the appropriate time, that wouldn't do just fine watered and weeded well once a week. Other factorss being correct, of course.

I have a distant garden that I tend at most once a week. I have grown almost every vegetable and have not had any problems. However the vegetables I have had problems picking on time have been zucchini, okra and beans.

Dean

Winter squash don't ask for a lot of attention -- unless the squash bugs and vine borers are bad in your area.

Like Dean said, if you don't have to pick fruits, most garden vegetables (onec established) don't need more than once a week maintenance. The thing is that you have to water them deep, from root not by sprinklers. When plants cannot find water near surface, they go deeper and deeper to get moisture. This method has an added advantage that more nutrient can be found there, because everytime you water or rains, some of the nutrients -especially nitrogen - go further down.
Also by good mulching one can prevent evaporations, soil dry out and weeds growth. Only the potted plants need more care.

Peas are easy to grow, although they can be a good bit of work to harvest since they're small.

Once established, Swiss Chard is pretty maintenance free, as is kale. Harvest the leaves and leave the stems and some leaves, including the old, coarse ones (to keep the plants going). In a few weeks, the plants will be ready for a nother "scalping".

If you have chipmunks, don't bother w/tomatoes, for the munks will eat every near-ripe tomato :-( unless you have a roaming cat.

The biggest challenge would be getting things to grow from seed, since just-germinated seedlings are apt to croak if moisture is lacking. However, shade cloth could be helpful.

Use mulch to retain moisture. (Unfortunately mulch is much loved by slugs). Aparently Sluggo® is cleared for organic growers. (According to the manufacturer, the active ingredient, Iron phosphate, is mined, and the inert is wheat gluten). I haven't used it yet, so can't say how effective the bait is.

Here is a link that might be useful: OMRI on Sluggo®

Corn is tough. Sow directly into the soil and forget about it, maby water it on a dry day. But it will take care of itself.

canuckistani

I had to laugh at the thread title because the first thing I thought was we wouldn't need to tend many plants if there weren't diseases and pests and weeds.

But folks have done a pretty good job at highlighting plants that do pretty well even with those problem abounding.

Jerusalem artichokes don't have to be taken care of, except perhaps in the most extreme conditions.

Rhubarb, herbs, potatoes, carrots, beets, pumpkins and squash. Most perennial and root vegetables will give you leeway, even during harvest. I find peas and beans as intensive as toms and such since they have such a small ideal harvest window.

If you have any significant quantities of any "easy" vegetable, though, you're going to have to tend more than once a week AND if it's hot, you're going to have to water more than once a week. Vegetable gardens are work, plain and simple. You can't shy away from that and get great results.

If you have chipmunks, don't bother w/tomatoes, for the munks will eat every near-ripe tomato :-( unless you have a roaming cat.

ppod, we have had chipmunk(s) living very close to my tomato garden. Last year, I had 10 plants and the fruit only gotten eaten 1 time by 1 animal, and that was a deer (hoof prints in the ground as proof). I haven't had any problems with chipmunks other than lots of holes that they love to dig in my garden and the potted plants. Grr...I don't like them much, but I'm thankful that they don't go after my tomatoes.

Catman, lucky you! For years the monks left my toms alone, but no longer.... grrr

Let's up the ante shall we? Although the season makes a big difference (Obviously, if the two weeks are in February, any plant will do. Two weeks in May or August? That is tougher.), there are many plants that can just keep going on their own, thank goodness. For lettuce, if you are taking leaves often, you need to keep doing that. But garlic is strictly a "fire and forget" garden weapon.

Considering pest problems, water requirements, and plant staking/etc., you could probably plant an absentee garden of garlic, sweet potatoes, and potatoes. Just plant and let it go until harvest. That practice is actually not uncommon where I live. Vast fields of sweet potatoes are grown in remote areas and are generally left alone.
Here are some plants and how long I could just totally ignore them.

Two weeks
potatoes, broccoli, radishes,

Three weeks
carrots, daikon, chard??, turnips,

A month
soybeans

Ignore until harvest
Jerusalem artichokes, sweet potatoes, garlic, onions, asparagus, strawberries

The easiest one for me to grow are Beets, Swiss chard, sweet peas, mustard green, cucumber, zucchini(harvesting should be regular), cilantro, mint... almost any herb including sweet basil, cauliflower, onion, leek, fava beans.

It must depend on your climate. My allotment is down the road a bit and I rarely go there more than once a week. The main problem, as others have said, is harvesting rather than 'tending'. A two week holiday in August means a jungle when I get back.

With all due respect, I can't imagine why you wouldn't want to get into your garden on a daily basis. I can't wait to get home from work and see another new tomato, or little tiny pepper just shedding it's flower. Just tonight, having been gone all day, and getting home at dusk in the rain, I went out to weed a little, and found enough lettuce to make a little salad.

I'm also thinking Sweet Potato. It is a perennial plant, that also vines out, to cover fences, trellises, and also works great as a ground cover! Sweet Potatoes can survive drought, sudden climactic shifts, root disturbances, and much more, plus it gives you those amazing morning-glory flowers, as it is in the same family and genus as other Morning Glories. The plant gives you those sweet, dark orange, edible underground tubers/corms, that, in turn can be dug up and planted in a new location for a whole new genetic copy of the original plant.

Of course, all you need to do to plant them is to buy a generic brand sweet potato at the store, plant it in the ground, and watch it grow!

There are some "superior" hybrids and cultivators of this plant, like the extra-sweet, soft-textured white sweet potato, but these can get very expensive and may not turn out to be as good as once-thought.

I can think of several reasons why a person might have a once a week garden.

A person might travel for business and only be home periodically.

The garden might be at some distance from the house: in a community plot, on a piece of land other than the residence, at a relative's place, at a weekend cottage, ... .

A person might work long hours or odd shifts and only see home in the daylight once a week.

A person might have family commitments such as kids' activities or care of an elderly/disabled person that leave only one personal day for gardening.

If we had the piece of "country" land we've long wanted to own I'd put some low-maintenance garden stuff like interesting and ornamental winter squash, sweet corn, or peanuts on it to split between home use and a cash crop. :-)