Clean or Dirty?
- Students will be able to test compost for nutrient levels.
Tools & Materials
- Compost screen
- Soil testing kit
It’s hard to argue against using compost in the garden or Lab as a soil enhancer. The nutrients and organic particulates along with the larger organic matter provide several benefits for the soil and plant production.
But not all compost is the same. The inputs used to create the compost influence the nutrient profile. Mushroom, cattle manure, and vermicast will all have different profiles and as a result different uses. If your soil is deficient in nitrogen then it would make sense to amend with a compost higher in that nutrient.
Screen some of your finished compost to remove any inputs that may not be fully composted. Perform a soil test on the compost to measure the nutrient (NPK) levels. How do those compare to your soil? Understanding the nutrient profile of your compost will help you better utilize it to get the results you want when using the compost as a soil amendment.
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