Should you have a marginal soil on your intended garden area, this article gives some good advice on how to both rebuild it or how to make new soil in an area without the necessary balance of nutrients, bacteria and fungi.
http://articles.mercola.com/sites/articles/archive/2016/08/28/soil-restoration-techniques.aspxThis could be the difference between surviving and not.
It does offer the chance that a (cheap) property that has been judged to be "unfarmable" may in fact become usable after a season of work to rebuild it. Live on your preps while you build soil for the next seasons crops.
[edit] spelling