• City of Tacoma QA
  • City of Tacoma Data




TAGRO Nutrients

TAGRO Nutrients Measured Annually

A&L Great Lakes Laboratories, Inc., tests biosolids produced at Tacoma's Central Wastewater Treatment Plant every year to determine the level of plant nutrients. The chart below lists 2012 averages, which are not guaranteed as with commercially produced fertilizers because TAGRO Mix, Potting Soil, and Aged Black Bark are organic products.

Nutrients

TAGRO
Mix

TAGRO
Potting Soil

Aged
Black Bark

Total Nitrogen

1.4%

1.1%

.25%

Available Nitrogen

.24%

.11%

.25%

Phosphorous

.85%

.65%

<.0033%

Potassium

.19%

.19%

.047%

Ph

7.9

6.5

5.5-5.9

Carbon-Nitrogen Ratio

14:1

28:1

80:1

 

Learn more about how we make and monitor the safety of TAGRO.

 

Technical Report

2004 Washington State University Cooperative Extension study: Suitability of Recycled Organic Materials as Growing Media, Micronutrient, and Phosphorous Sources for Container Nursery Stock Production

 

This report details the use of yard debris, biosolids and animal manure composts as growing media, paying careful attention to each product's use of water and nutrients. Recycled yard debris, dairy manure compost, TAGRO, Douglas fir bark and GroCo were used to grow rhododendron and lilacs according to standard nursery practices. TAGRO was deemed a sufficient growing media.