Soil testing ensures fertile soil without excess fertilizer by determining soil nutrient levels. One should divide fields into uniform areas and collect subsoil samples from each to test for nutrients like phosphorus, potassium, pH, and micronutrients. Season extension methods like cold frames, hoop houses, and row covers allow growing vegetables earlier and later by sheltering plants from cold and capturing solar heat. Planning techniques such as vertical gardening, succession planting, and intercropping maximize garden space.