Decades of research and demonstration prove Loop is good stuff that builds good soil. Not only do gardeners swear by Loop, but long-term demonstration plots show it can grow more wheat than synthetic fertilizer.

Loop also grows big trees and lush lawns. Loop has been used to reclaim degraded lands like mine tailings and compacted logging roads. Loop brings life back to lands where once nothing would grow. Loop is a “complete plant food” containing the 16 elements considered essential for plant life – and generally in the same ratios that plants require.


Nine of the 16 essential elements appear in higher concentrations in plant tissues than other nutrients. Starring, in order of appearance: Carbon, oxygen, hydrogen, nitrogen, potassium, calcium, magnesium, phosphorus, and sulfur.

Carbon, oxygen, hydrogen, nitrogen, phosphorus, and sulfur are all components of amino acids and proteins necessary for critical functions in plant cells. Nitrogen and potassium are important for photosynthesis and energy production. Magnesium is not only a piece of chlorophyll molecules; it’s also needed for protein synthesis and hundreds of enzyme reactions. Calcium is important to cement plant cell walls together and for cell division.

Most soils and crops need nitrogen supplements. But adding too much of it can cause nitrate leaching and water contamination. For this reason, nitrogen is the most important nutrient in determining land application rates of Loop. Rates are determined by assessing the amount of nitrogen needed by each crop and matching that with the amount of nitrogen available in each batch of Loop.

Loop typically contains 6 to 7 percent total nitrogen. Ammonia nitrogen, about 17 percent of the total nitrogen, is a water soluble form of nitrogen that is readily taken up by plants. The remaining nitrogen is bound in organic matter and is sometimes referred to as slow-release nitrogen because the organic matter has to decompose before the rest of the nitrogen becomes available for plants.

For more information on nitrogen, see Managing Nitrogen from Biosolids at the Department of Ecology Website.


West Point
Treatment Plant
South Treatment
Brightwater Treatment

Ammonia Nitrogen 0.8% 1.2% 0.9%
Organic Nitrogen 5.0% 5.3% 5.0%
Phosphorus 1.6% 2.5% 1.6%
Potassium 0.1% 0.2% 1.4%
Sulfur 1.7% 1.1% 1.1%


Micronutrients appear in plant tissues in smaller concentrations than macronutrients, but they are still critical to sustain plant life. Chloride is known to stimulate photosynthesis while iron is necessary for chlorophyll production and respiration. Boron is essential for developing roots, seeds, and fruit. Manganese is needed to metabolize nitrogen and zinc is needed to make growth hormones (auxins). Copper is for chlorophyll synthesis and molybdenum is required for vitamin C synthesis and symbiotic nitrogen fixation with soil microorganisms. Micronutrient deficiencies have been known to severely stunt growth and reduce yields. Loop is awesome because it contains all the micronutrients for healthy plant growth.