I'm not sure about seeds, but I bought a nopal (paddle cactus) from the mexican grocery store for like 5 cents, and put it right in the ground, and its now growing very nicely.

I've been using my grocery store as my seed source for years. A few species (pears, cherries, apples) might not grow for you; that's just because you've purchased wide crossed varietals that have sterile seeds. their inability to grow is not due to lack of love or trying on your part!

I just ran across a book at my local library called "Don't Throw it, Grow It! 68 Windowsill Plants from Kitchen Scraps", by Peterson and Selsam.

It's perfect for what you're trying to do. It describes what portions of the food to keep, if there's any pre-work that needs to be done in order to get the seed to germinate, and what method is best to get the roots to form (e.g. soil, water or pebbles).

I'm going to try myself. Best of luck!

We're growing tomatoes, lemons, and grapefruits this way. I think the lemons were organic (I feel like this might make a difference?), though we've still had pretty mixed luck with citrus. But the tomatoes have really shot up. I assume that whatever fruit they produce (if any) will by un-hybridized, but that's part of the fun.

I would ASSUME that farmers' market produce is a better bet for this kind of thing, though. Next chance I get, we're starting some hot peppers.

We tried peaches, but it didn't really take off (yet). Avocados work, actually (my father's done that), but it takes a couple tries to get one that doesn't just die right away.

Most grocery store varieties of common produce like tomatoes or peppers are bred for being hardy in standing up to transport. So, myself I would opt to buy seeds intended for garden use, because they're bred for tastiness and garden-suitability instead.

I'm a die hard gardner and I still buy my tomatoes and peppers as starts. If you don't know of any good nurseries around you craigslist tends to have people selling their extra starts come spring.

Hybrids are plants that are cross pollinated between two same or similar species. Many times the offspring will be sterile as in the case of a mule (cross between a donkey and horse); sometimes not.

Veggies from the grocery store may be hybrids or, in the case of non-organic, genetically modified. Again, gm plants may be sterile or not.

I'm not sure if I would want to grow gm corn or gm strawberries. Any good read on the internet will tell you why.

In the case of nearly all fruit and nut trees the plants are grafted onto a different, more hardy, root stock. A super hardy, selected for the intended climate zone, but less desirable for fruit production, tree is cut off below the lowest branches and a better fruiting tree is grafted onto the top. Many fruit trees started from seed may not be hardy enough to grow in your climate zone without the grafted root stock. In addition your tree might be a hybrid which may or may not be sterile.

If you buy what is called "Heirloom" varieties the chances are much better that you will be successful in getting something to eat. There are no regulations for the word "heirloom" as pertains to plants or veggies so you need to take the seller's word for it. You can waste a lot of time growing some nice little plants or trees and never get fruit or veggies.

Seeds are pretty cheap. There are tons of resources for organic, non-gm, and heirloom seeds. Fruit trees are more expensive but then you know you'll get fruit instead of a decorative tree.

Don't mean to be pessimistic but there is a reason that people who are experienced gardeners generally buy seeds, started plants, or harvest their own, non-hybrid seeds from crops of reliable sources.

My one comment is that if you're going to go to the trouble of trying to do this - go with organic heirloom vegetables (found at many farmer's markets) - because doing this with standard supermarket fare is usually a waste of your time.

Besides the issue of sterile seeds you'll also run into the issue of irradiated produce (another reason to go farmer's market).

Also some things, like the Russian garlic I bought at my local farmer's market and some ginger, work fine to plant in a pot. The garlic I used as many cloves as I needed and then popped the others into a pot; I generally cut off how much ginger I need - let the cut air dry for a day - then pop it into the pot (though it's easier to just pickle leftover ginger) but since so many things like potatoes and garlic have been treated they won't necessarily sprout for you. I always give it a try but only as an experiment (never relied on). Starter plants are a better bet if you're going to 'rely' on it as your food for later in the season.

I agree with everyone that said saving supermarket seeds is probably not going to get you the tastiest veggies in your garden. That being said, you will probably always have the best luck with seedlings. Someone has already given the plants a good head start for you. Starting from seeds can be finicky, but it's absolutely not impossible. You just have to start them indoors and depending on where you live, it's getting a bit late in the game for starting seeds and having them ready in time to plant outside.
I recommend getting your seedlings from the farmers market, but you can find tomato and pepper seedlings most anywhere. I don't have a yard but I do some container gardening with tomatoes and peppers and herbs every year on my balcony and always have great results. Then, at the end of the year, you can save some of your own seeds and try to start from seed next year.

I always save my potatoes that are starting to sprout and plant them in the garden. They always produce - and there's nothing like homegrown new potatoes! Ditto for pumpkin and pepper seeds. I've had less luck with cucumbers and tomatoes.