Elle, I feel your pain and everyone has given you great advice. After reading everyone's comments I want to ask what have you done to improve your soil?
I don't have soil so I started growing stuff in caliche.
From Wikipedia: "Caliche is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt."
Dear hubby found a deposit of clay to which he added store-bought garden soil, store-bought well-composted manure and leaf mold from under our oak trees. This was all mixed in a wheel barrel and added to raise beds since it is very windy where we live.
I also add all our spent coffee grounds, occasionally.
Making compost to add occasionally will also help.
I learned a lot from Dr. Bryant Redhawk so I would like to recommend his soil series: