Answer: You are on the right track with adding organic matter to the soil on a regular basis. In addition, you may need to add other amendments such as lime to correct the pH if you have very acid soil, or supplemental amounts of nitrogen and so on. The only way to know for sure what to add is to run some basic soil tests and see what (if anything) your soil is lacking. Your County Extension (696-3500) can help you with the tests and with interpreting the results.
Since you are adding leaves, several additional thoughts crossed my mind. You should avoid adding leaves from a black walnut tree as many plants find them toxic, particularly tomatoes and their relatives. You should also remember that a vegetable garden does best in full sun all day and away from competing tree roots -- if you have large trees it is possible that their roots reach beyond their branch spread.
Good luck with your garden!
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