To create a self-sufficient soil for gardening in the long term, you have to make it healthy with the use of organic matter. You can also prepare an organic fertilizer with 4 parts blood, 2 parts bone meal and 1 part kelp or rock phosphate. Adding bone and blood meal to coir (coconut husk) also acts as a good fertilizer. If you live near a parking lot or busy road, compost help reduce lead levels and maintain a PH of 6.5 to 7. Double digging trenches and raising compost beds will help improve soil texture and density.