Soil texture is determined by the proportion of each of the different-sized particles it contains. Few of us are blessed with loamy soil. Most of us deal with a soil containing too much clay or too much sand. Clay just needs to be kept aerated so it does not compact and develop drainage problems that suffocate and rot plants. To improve clay, double dig your vegetable or flower garden.
Sandy soils have problems retaining moisture and nutrients.
Work in ample amounts of organic matter and keep two inches of organic matter on top at all times. Be generous with the mulch, and try frequent, smaller fertilizer applications. All soils should be tested and amended according to nutrient needs every two to three years. Invite earthworms to dig and improve your soil. Then pick plants that can survive in what your yard offers.