I realize this is a 3 month old thread, but it is something I have thought of often. No doubt knowing what chemicals or lack of chemicals is important, but its tough to ignore the cost going into the garden as well. As enjoyable it is to harvest my own produce, I have very poor soil that requires a lot of maintenance. Finding and planting things that grow well in your soil, while avoiding things that do not grow well can take a dent out of our pride, but may be the possibility of trading food with people you know. Always be on the lookout for deals at garage sales and craigs list for gardening tools, etc. If time that you spend in the garden is enjoyable and is not a factor, then that is great. Me on the other hand would rather find easier and quicker ways to grow and harvest food. Using plastic sheet material to warm the soil and suppress weeds is one of those ways. Finding cheap or free plastic material would be even better. All in all, its tough to put a value on the entire gardening thing, but I suppose its possible. Calculate the amount of tomatoes, potatoes, carrots, etc and the supermarket price of each one, minus the fertilizer, water, etc to get a rough idea. There will always be plant losses due to frost, heat, etc, but planting your own seeds in the house or greenhouse can help offset the cost. Best of luck to everybody. Mike's Plans.