During the summer months, we hire FFA students to help with garden chores, such as stacking wood, moving gravel, hauling away wheel barrows of weeds, mowing, etc. Recently, I asked this season’s helper to sift some compost before putting it on a new section of garden. “Why are there shells in your garden”, he inquired. Now, if he were from Rhode Island, rather than West Virginia, he would have asked,”Why are there quahaugs in your garden”. Quahaugs are large clams from the Narragansett Bay. The shells are in our garden to slowly release calcium into the soil. I put them there because, when we visit family in Rhode Island, I collect bags of various types of shells from the shoreline to bring home for the garden.
Recently, I have been reading about the benefits of seaweed supplements for crop soil. This usually comes in the form of liquid concentrates or powders to mix with water. On our recent trip to Rhode Island, I noticed a lot of seaweed washed up on short after a storm. Tempting, but I restrained myself from filling the trunk up with seaweed for the compost pile. Shells are easier to wash and bag up.
This begs the question of what forms of nutrients do we add to soils to increase fertility? Agricultural societies have tried various methods over generations. Some cleared land, farmed out the nutrients, then moved on to new forests or grasslands. Others stayed in a region, and rotated their crops, leaving some fields fallow. Others added manure from livestock, and left plant stocks and leaves to decay into organic matter. Western economies in the 20th century accepted the slogan “better living through chemistry”, relying on synthesized fertilizer sprays and granules to boost soil production. The organic farming methods used non-synthesized methods applying mixtures of manure and/or seaweed slurry.
This reminds me of parallel debates about the best way to maintain personal nutrition. The pharmaceutical producers identify specific chemical formulas and the health-food industry grinds up various plants to provide pills and powders to add to our meals. There are labeled as “dietary supplements” implying that they do not substitute for food. Many of the nutrients packaged in pill format are available in a balanced diet. Do we benefit in some way from eating the whole food, rather than extracting out the specific vitamins and minerals?
In terms of personal health, I see several benefits. First, eating the food stimulates the digestive system and requires more time than dissolving a pill. This allows the intestines more time to absorb the nutrients, rather than washing them out. Second, eating the whole food provide more fiber, which helps to clear the gut of the waste products that the body cannot absorb. Third, whole foods are more likely to have bacteria desirable for digestion. Those colonies of bacteria in our guts help us extract more vitamins and minerals for our health.
Back to the garden, the question arises, does the soil benefit from it own form of whole food? I believe that the same processes occur as with our personal nutrition. When whole manure, compost, or plant and mineral matter (those shells) are added to the soil, they may take a season to years to decompose. The nutrients contained in those items are released more slowly, reducing the amount farm run-off which into streams and rivers. Allowing whole plant matter to decay into the garden (or to be added in the form of compost) increases the organic density of the soil. This retains water and provides carbon for fungus to grow. The colonies of fungus connect with the plants’ root to transfer water and nutrients from the soil.
If we use synthetic vitamins and minerals, or field fertilizers, we are risking that much of these are water-soluble and will leach out with a drink of water, or the next rain. If we use similar organic nutritional supplements and fertilizers, we still risk that water will wash them away. Also, taking a pill does not provide the fiber nor beneficial bacterial (except for a pro-biotic pill).
My conclusion is that covering the garden in goat-barn hay and manure, piling leaves from the dirt-road ditches, and tossing shells into the mix will provide for health soil in our garden. I’ll have to figure out how to stuff my suitcase with seaweed.