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Organic Fertilizers: A Double-Edged Sword for Water Sources
Organic gardening has been gaining popularity as more people are becoming aware of the health benefits of consuming food free from pesticides. However, even organic fertilizers can have negative effects on water sources if not used correctly. According to Bradley Secraw, a Cleveland County Oklahoma State University Extension agriculture educator, moderation is necessary when it comes to the use of organic fertilizers.
There are three categories of organic fertilizers: plant sources, animal sources, and mineral sources. Compost, derived from plant or animal sources, is the most popular organic nutrient source. However, it is classified as a soil amendment and not a fertilizer. Soil amendments help improve the physical properties of soil, such as water retention, permeability, water infiltration, drainage, aeration, and structure.
Commercial compost additives follow a 1:1:1 analysis, containing 1% nitrogen, 1% phosphorus, and 1% potassium. As an amendment, it is not harmful to crops. However, if used as a fertilizer, the ratios for growing crops are thrown off. One inch of coverage over a 1,000 square-foot garden requires 84 cubic feet of compost, which offers 3,100 pounds of compost per 1,000 square feet.
This kind of compost will add 30 pounds of unnecessary nitrogen if used as a fertilizer, harming crops. Additionally, these mixes also offer too much phosphorus and potassium, which can harm growth or run off. Nitrogen, in particular, does not bond to the soil, so it leaches through the soil profile and ends up in the groundwater.
Secraw warns that the scale of operations matters when it comes to the use of organic fertilizers. Small farms may not consider themselves a threat to the environment because of the scale of their operations and because they use organic fertilizers and soil amendments. However, if these small gardens and farms were scaled up to hundreds or thousands of acres, the individuals engaged in these practices would inadvertently contaminate groundwater and surface waters.
In conclusion, the use of organic fertilizers is not without its risks. Consumers should follow recommendations for fertilizer quantities to maximize results and prevent runoff. While organic gardening has many benefits, moderation is still necessary to prevent harm to crops and water sources.
https://www.yahoo.com/lifestyle/home-ag-organic-fertilizers-still-135100078.html
