I am a proponent of growing as much of your own food as you realistically can within the constraints of your lifestyle and space considerations. Besides being enormously satisfying, it is the only way I know to economically eat organic produce.
One approach to gardening that addresses both the issues of time and space availability to a substantial degree is the square foot gardening method. It was started by Mel Bartholomew 40 years ago as a way to maximize the yield of small space gardening. And it’s been going strong ever since.
In fact, Square Foot Gardening has been our family Bible for gardening for some 20 years now.
I started with it way back when my kids were little, and I wanted to give them the opportunity to experience the satisfaction and wonder of growing something on their own.
It was the perfect book for that then, and we've used it ever since to "farm" our small, urban yard. I highly recommend it. And apparently the new edition offers even better ideas for saving time, effort, and water.
I don't actually buy many books any more now that my kids are grown - I prefer to use the library - but this invaluable reference is definitely a worthwhile exception.