Learn About Inputs in Organic Farming

Why It's Vital to Certification

tractor dumping manure
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In the agriculture business, the term input is defined as any sort of substance used by a producer for pest control or for soil fertility management. For example, inputs may include soil amendments such as lime, mineral calcium or compost. Some farmers may use animal by-products such as fish emulsion, fishmeal, blood meal, bone meal or meat meal.

Inputs can be certified organic approved or not. As an organic producer, you must use only approved inputs. In general, synthetic substances are prohibited, but there are some exceptions. The National Organic Program (NOP), which establishes the standards used by the USDA for organic certification, maintains the National List of Allowed and Prohibited Substances. This list tells you which synthetic substances are specifically allowed and which natural substances are specifically prohibited.

Natural vs. Synthetic

The NOP considers allowable natural inputs, or nonsynthetic inputs, to be any kind of substances that occur naturally in plant, animal or mineral form. This can include crop and animal residues. Natural inputs also include substances that are created through a biological process that naturally occurs – for example, vinegar.

Some natural inputs that are specifically prohibited are products derived through genetic engineering, as well as contaminated organic materials, such as conventional cottonseed meal, which contains pesticides, and leather meal, which contains the heavy metal chromium. Biosolids, such as sewage sludge, and certain other products, including ash from manure burning and tobacco dust, are also prohibited.

Prohibited synthetic inputs are classified as products produced by a chemical process or natural products that were chemically changed, such as certain mineral products created by adding acids to natural minerals.

Before You Use Inputs

Just because the input is allowed per the National List doesn’t mean you can freely use it. The National Organic Program stipulates that producers must try other natural means to address production needs before you resort to using inputs. For example, if you need to improve your soil fertility, you might first try crop rotations or green manure cover cropping. If you have a pest problem, you might introduce natural predators of that pest or try lures and traps. If you need to reduce weeds, you will try mulching or hand weeding first. If these preventative methods or cultural practices don’t work, then you can opt for inputs on the National List.


It is vital to sustaining your organic certification to track all inputs and ensure they meet organic standards. If you use a prohibited substance such as a fertilizer or pesticide, you could lose your organic certification for the affected area for up to 36 months. Before you consider introducing any kind of input into your organic production process, consult the USDA regulations. You can also consult with the Organic Materials Review Institute (OMRI), which is a nonprofit organization that helps organic producers find approved input sources. OMRI reviews products to determine if they meet the regulation standards and, if so, classifies them as “OMRI Listed.”

Organic growers must keep a record documenting all inputs, including the location where inputs were used, dates and amounts. If you need a clear and concise way to track field inputs. You also need to retain documents such as purchase receipts, product labels, lab analyses, and soil tests.