"I'd love to grow a garden but I just don't have the space!" Have you heard this uttered before? Have you uttered it? Well stop it.
Above are a picture of my original garden in the pots and planter, and my current garden the year I moved in.
I've mentioned before that the word garden isn't defined by size, both a balcony with potted plants and the great gardens of the world are considered "gardens". Space means nothing. If you absolutely have no outdoor space to call your own, there is always the option of a windowsill garden on the inside, or a window box outside, or just growing some house plants. So long as a window garden is south facing it will grow. You live in a basement or jail cell with no outside view? Why not pick up a broad spectrum lamp and make a closet into a grow room? No closets free? At this point you should probably opt to grow mushrooms (which are delicious and surprisingly easy to grow, and totally tradable to your neighbor that grows tomatoes). Thanks to technology options for growing plants in unusual ways are available to just about anyone. My initial gardening experience of three pots and a planter box was challenging but as my experience grows I'm better able to visualize what I can fit into a small space. My circumstances have changed since then and I now have a total of 102 square feet of garden space that produces over 200 lbs of produce in a season. That's equivalent to a 10'x10' garden, but because I'm working in a small space with several obstacles my garden is actually made up of 2 - 4'x8' beds, a 4'x4' bed, two half whiskey barrels, a 10'x2' strawberry bed, and several trellises.
The second picture above shows the four feet of lava rock between patio and fence at my current home, before I put in the raised beds. It looks like a useless expanse of terrible rock-filled soil that could never become much more. Below is a photo of my 2011 garden.