Answer: Since it was once a truck farm, you'd expect that the soil would be wonderfully rich. However, I'd be concerned about the area that won't support vegetation. It might be worth the time and trouble to have the soil tested. Perhaps it was a site where petroleum products or animal waste or excess pesticides were dumped. If so, you wouldn't want to garden there. You can contact a private soil testing lab or sometimes state universities will offer soil analysis. It might be that the soil is contaminated and not fit for growing things, or it could be that it is simply depleted and all you'll need to do is incorporate some organic matter.
Look in the phone book under "county" for your local Cooperative Extension office, or find a private soil testing lab. Once you have the results back you can decide how to fix the problem.
Best wishes with your garden!
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