Let’s compare organic amendments

A livestock farmer appreciates the value that manure has to their cropping system. In the past, cash crop producers, who did not have access to such a beneficial organic soil amendment were envious.  Now there are options to source and apply various different organic amendments,  but with many non-agricultural sourced materials on the market, it is important to know which product has the best fit to meet the needs of the individual field.

Value of Organic Matter

It is relatively easy to determine the fertilizer equivalent value of each material, but determining the dollar value of the organic matter (OM) is more difficult.  Organic matter represents up to 68%, or more than 1,300 lbs/ton in some of these materials.  The benefits of organic matter include:

  • feeding the micro organism populations, improving diversity,
  • increasing the nutrient-holding capacity of the soil (especially sand and clay),
  • increasing the water-holding capacity of the soil (especially sand and clay), and
  • increasing soil structure and aggregate stability that helps prevent soil erosion.

In the summer of 2010, the Middlesex Soil & Crop Improvement Association demonstrated the application of three different organic amendments:

  1. processed biosolids pellets
  2. N-viro
  3. municipal green bin compost.

Each product could be applied without requiring a nutrient management plan as they are regulated under the Canadian Fertilizers Act or are classified as an unrestricted compost. Each product had some unique characteristics that made it a good fit for some specific conditions.  Samples of each material were taken for analysis so that each could be easily compared.  The macro and micro nutrients that they would provide (in lbs/ton as applied) is shown in Table 1, as well as organic matter additions, pH, bulk density and C:N ratio.

Table 1 Nutirent value of various solid organic materials

Processed biosolids pellets are an excellent source of organic matter, nitrogen, phosphorus and micro-nutrients, but are not the product of choice if potash is an important requirement.  This product would not be a good choice for fields with low potassium fertility, or alfalfa forages with an aggressive harvest schedule, unless the field was supplemented with potash (KCl).  Processed biosolids are available from Windsor and Toronto and are similar in content The processes used at the water treatment plants do result in some differences in aluminum, calcium, iron levels that could affect phosphorus availability, especially in low pH soils.

N-Viro is also a biosolids material.  It is processed with kiln dust to provide a liming benefit to fields.  The high calcium and potassium indicate availability of liming capacity from the kiln dust, making this product ideal for sandy soils with low pH levels.  Nitrogen contribution and organic matter per ton is relatively low.  Planting immediately after application should be avoided, especially on dry sandy soils, since high salt content could lead to seed-burn.  N-Viro should be applied on a wind-free day, because it is dusty.

Municipal green bin compost is a high organic matter product with a good balance of available N-P-K and micro nutrients.  With a bulk density of about 20 lbs/cubic foot, the odour and consistency of the compost used in this demonstration was similar to corn silage. This type of compost is easier to apply uniformly than most solid manure types.  Municipal compost is a uniform material that works well when applied once in the rotation (i.e., after cereal harvest in the fall) at about 10 to 15 ton/acre.  Hamilton, Peel, Ottawa,  Thorold, Arthur, Durham, Guelph, London and other regions also have municipal green bin compost programs available or in development.  Analysis will vary slightly for each facility, depending on the process and length of time materials have been cured.

There is a range in cost of the materials compared in Table 1.  The price is determined mainly by distance transported, application and volume.  Representatives and their contact information is listed below  for each product  type.


Windsor Processed Biosolids Pellets:  Harry Buurma – 519-849-5010 buurma.family@gmail.com

N-Viro – Ian Shipley 519-786-2106  or Lise LeBlanc 519-410-3228  lise.leblanc@n-viro.ca

AIM  Environmental Group – Hamilton –  Frank Peters  fpeters@aimgroup.ca   or Mike Lishman 289-260-6820  arlington.farms@live.com

London Municipal Greenbin Compost –Travis Woollings 519-317-6756 twoollings@rogers.com

Peel Region Compost – Matthew Stevens 416-807-4125 matthew.stevens@peelregion.ca