IMO, one to a pot. Get more pots, larger than what you have, especially for the tomatoes. There is a "Growing from seed" forum here and also "Beans, peas and legumes", as well as "Vegetable gardening" and "Tomatoes". I'm not trying to offend, please don't take it that way. It's just that you're asking a lot of questions after the fact, and there is a plethora of information on these forums. Doing your homework before you plant will help you maximize your crop. You need to decide how many plants of each you want/need, and separate them or cut off the unwanteds, and pot them up to larger containers. And yes, pics would help. You need to open a photo sharing account(free)at a site like Photobucket and download your photos to your account. Then copy the HTML code below your thumbnails and paste into your message. When you preview your message, the photo will show up.HTH

Rob, how were you thinking of planting these ultimately? How much room to you have?

It sounds as if you were very enthusiastic when starting, but I'm guessing this is your first year growing in containers. It's definitely not the more the merrier for most plants, though they do vary tremendously regarding how large of a root system they create and how much water they require. The root system and the water required are both part of deciding what size container to use; if it requires a lot of water and you'd have to water it 10 times a day to provide that, it wouldn't work well.

As Noinwi has pointed out, the containers you have are likely not appropriate for all of your plants.

I primarily grow in Earthboxes, but just for a reference point, 2 tomatoes are grown in one box and that box contains 60 dry quarts or 2 cubic feet. My guess is that one of your containers does not contain a cubic foot of soil-less mix. Beans need much less space (pole especially) - 16 pole beans can fit into an Earthbox. Only 4 cucumber plants can, however, so again, I doubt they will work in your 12" containers.

Culling them is easy, but first you have to know how much space each requires and if you have the space. Once you know how many you can have and have correct sized containers for, remove the plants that are weak, spindly, have discolorations, or otherwise seem less strong than the other plants. Keep the strongest. It depends on how old they are, but if they are young enough, you should be able to easily pluck them out, roots and all, then toss them.

Do be careful when you transplant the other plants. It's probably worth doing a bit of research on how to transplant. Tomatoes are handled differently from beans, for example.

Use a pair of scissors to remove all but one plant per pot. That will do the least harm to the root system of the remaining plant. You might want to give a little tug on some of them to see if they come up readily, though.

12 inches is awfully small for veggie production.

Very helpful advice given in the above posts.

Hey if you need pots go to the local garden center and schmooze the manager and Im sure that they have a ton of 10 gallon buckets that are not being used!!!!! Hope that helps its what i did see pic below:
{{gwi:28504}}

Thank you for your responses. noinwi, I put in my gardern first, then decided I should get some expert advice. Wrong order of events ! LOL

Lathyrus, thanks for the reference to the Earthboxes. I am now assembling a few of them.

Here is a pic of my watermelons, to see if I I can post pics:

http://s935.photobucket.com/albums/ad198/rob043055/?action=view&current=watermelon.jpg&newest=1

I hope you enjoy the Earthboxes as much as I do. When I moved from country to city (and in a high rise condo), I thought I'd never garden again. I'm so happy to use these on my deck.

I have, over time, changed the soil mix I use, however. This year I'm using a combo of the "gritty mix" (search ion it for more info) and potting mix. I found I needed some peat to get the wicking I need, but that having at least 50% of the gritty mix keeps the mix less wet. My plants are happier for it.