When I started my gardening adventures, I planted directly into the ground but ran out of space and would not be able to fit the tray of plants I had started. I also wanted to have better growing conditions than my rock hard clay soil and by bringing in containers to fill with potting mix seemed easier and made more sense for me at that time. I have almost off my plants except for a few Eggplants and Bell Pepper plant as these are in my newly built raised bed.
The containers can be pretty much anything but there are some minimum size recommendations. Most plants will not fruit until it feels anchored and a larger container may be needed. I am not saying you need a massive 20 gallon pot. Although if you have a dwarf tree of any sort, I have a kumquat tree, you may need one but most plants are fine with a 5 gallon pot.
Google brings up over 660,000 results for container gardening that may be more informative and much more thorough than I am and I invite you to read more than my 1 post. You will find A Guide to Container Gardening, a chart that shows minimum size requirements of containers for certain plants, here and many other pages.
Containers can be expensive, cheap or even free and who says they have to be ugly? Your creativity should be expressed. Stickers, paint, bottle caps and many other things can help spruce it up. Your imagination is the only thing hold you back when decorating these containers.
I have used a rectangular salad container to start up some beet seeds and once they got big enough, I put them in the same container as my kumquat tree. The pot is so massive that the tree has room around it for more vegetables and this shows how one pot/container can be used for multiple things, if it is large enough. If you have started your own seeds, possibly in your egg cartons or just in small containers, they may need to be transplanted into bigger pots at some point. Of course, the amount of available room for your garden will dictate the size of your containers and may require some creativity but may still bring in some vegetables or herbs. I loved growing my own parsley and used it in almost everything I cooked but hoping to expand to more herbs for this following spring season.
Well, I think this should give you some ideas as to where to begin. I know I did not go into detail about everything but I tried to include some useful links in the post. I am always here to try and answer any questions. As I have said before, I do not claim to have all the answers and do not thin I ever will, but may be able to lead you in the right direction. I also invite anybody that has comments / ideas / constructive criticism to post a comment with their information or idea.
Thank you for stopping by,