Building a garden out of sand is challenging because sand does not hold moisture and nutrients very well. Much of the southeastern part of the United States is covered in sandy soil known as blow sand or sugar sand. At one time, the sandy soil covered the floors of the great southern forests and was constantly enriched by rotting organic matter such as fallen leaves and dead branches. However, as land was cleared for farming and development, the source of organic matter was eliminated and the sand became barren of nutrients and organic matter as the high rate of annual rainfall washed through the porous sand.
How to Build a Garden Out of Sand
Dig the sand out of the space you plan on making your garden to a depth of 12 inches, completely removing the sand.
Add a 3-inch layer of hay or straw to bottom of area where sand was removed . Adding a layer of hay or straw will prevent water from draining through the sand. Don't add too much because you'll want the water to slowly drain through and not sit on top of the hay or straw layer.
Add well-rotted compost to sandy soil removed from your planting area until soil is one-half sand and one-half well-rotted compost. The compost must be well-rotted because if it continues to rot in the sand, it will pull all available nitrogen from the fertilizer and soil to continue the decomposition process.
Mix twice the amount of granulated organic fertilizer that is recommended on the fertilizer bag. If you are not using granulated organic fertilizer, use the recommended amount of chemical fertilizer. Organic granulated fertilizer breaks down slowly and cannot burn plant roots like chemical fertilizers.
Add the soil mixture back into garden area and add plants as desired. After planting is done, add a 1-inch layer of mulch over any bare soil.