It does not take many calculations to figure if you save money for food with a small garden, you will save even more with a big one. That is true, but you need to figure in your time and tools needed. A larger garden takes longer to prepare and keep watered and weed free. At some point you might need a tiller or other equipment which adds to your costs. If you freeze or can your harvest, figure in extra time and the cost of equipment and supplies.
Start out with a small area. A couple of plots 4’ X 8’ plots can provide a lot of produce with a manageable work load. Start with a couple of tomato plants, some peppers, pole beans, lettuce and a few of your other favorite vegetables. At first avoid corn, potatoes and other crops that take a lot of space and are fairly inexpensive to buy.
Get to know a local gardener
A local friend or neighbor can offer a lot of advice. They will have an understanding of your local conditions that will be difficult to find in a book or on a web site. They might even have some extra plants they can give you, or lend the use of their tiller.
Expect some failures
In over 30 years of gardening, I have never had a year without some disappointments. We had a late spring, an early summer, or an early frost. It was too hot or too cool, and it rained too much or not enough. Maybe the rain just came at the wrong times. That does not even include insect or four legged pest invasions, not to mention various plant diseases.
The fact is that conditions will not be optimum for all of your crops. A long cool spring that is great for peas, lettuce and spinach will mean that your tomatoes and cucumbers will get off to a slow start. Growing conditions contributing to a great harvest for one crop almost ensures that another crop will be below par. Just learn to live with it.
Learn to start from seed
When you start out, you will probably need to buy some plants like tomatoes and peppers. Direct planting the other crops will save you a lot of money. With the price of some vegetable plants at garden centers, I wonder if you have a chance of getting the price back in your harvest.
I recently saw large tomato plants for $10 each at a well known discount chain. Smaller plants will adjust better to transplanting and are a much better value. One local garden chain sells six 4” corn plants for $1.70. Ignoring the fact that corn does not transplant well, I can buy six ears of fresh sweet corn for about the same price and without the effort and risk of crop failure.