3. Soil Amendments:

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Soil amendments are any materials that are added to soil to improve chemical or physical properties. While they are useful, if handled improperly, biological soil amendments can pose food safety risks, and  inorganic fertilizers can pose chemical contamination risks. If you are unsure whether your soil amendment is raw manure or composted, use raw manure practices just to be safe. Good record-keeping with the appropriate Logs is important to monitor and keep track of all soil amendments and composting processes under Standard Operating Procedures (SOPs).

a. Raw Manure:

Raw manure should never be applied during growing seasons  and should be incorporated into the soil within 72 hours of application. Intervals below:

raw manure
Raw manure pile
Crop Type: Recommended Application
Interval Before Harvest:
With edible portions that
do not contact soil
90 days*
With edible portions that
do contact soil
120 days *

* Refer to the Food Safety Modernization Act (FSMA)  Produce Rule for specific numbers as it applies to your farm.

Keep in mind that raw manure may also contact produce via runoff and wildlife/domesticated animals.

b. Compost:

Compost thermometer at ~135 degrees F (Lynn Nakamura-Tengan, 2015).

Composting reduces pathogen risks associated with raw manure but must be processed correctly. Before using equipment with composting, be sure to thoroughly clean and sanitize any equipment previously used in raw manure handling.

Process: Criteria:
Enclosed System
  1. maintain temperature of 131-170ºF for 3 days
  2. turn ≥ 5 times
  3. cured 45 days
  4. covered when finished
Windrow System
  1. maintain temperature of 131-170ºF for 15 days
  2. turn ≥ 5 times
  3. cured 45 days
  4. covered when finished

Proper compliance of practices is crucial for the safety and success of your farm. For more information and educational materials, watch the video below or visit Cornell University’s GAPs and Cornell University’s Produce Safety Alliance. Once you’ve familiarized yourself with this topic, you can move on to others!

Informative videos on the GAP topics provided by Carolina Farm Stewardship Association