Lambert Peat Moss takes great pride in evaluating its various peat bogs and identifying the best quality of peats that are required by each market segment, horticulture, agriculture, environment and leisure. Our peats are evaluated by the color and particle size of the peat.


The color of the peat is an indicator of the age of the peat and its degree of decomposition in the bog. This determination is made in the bog by trained technicians who evaluate the peat using the von Post Scale for assessing peat decomposition. The peat bogs are mapped and the peat is graded in each block or section of the bog. The peats are differentiated by color that corresponds with the descriptions used in the von Post Scale:

  • Blond/White Peat: Blond peats are found in the uppermost part of a peat bog. They are the youngest and least decomposed of the peats. Blond peats are very fibrous and spongy. They compress well and provide good air-water relationships when used as a growing substrate. They hold a lot of moisture and have a good cation exchange capacity (C.E.C.). These peats do become hydrophobic when dry and may be difficult to rehydrate. Blond peats are occasionally called “white” peats.
  • Brown Peat: Brown peats are intermediate in decomposition and lie below the blond peats in the bog. They are darker in color but still have good air and water retention properties when used in growing substrates. Most horticultural applications utilize a blend of blond and brown peats to provide greater consistency and uniformity for crop growing.
  • Black Peat: Black peats are very decomposed and contain no fiber. They are pasty when wetted and they do not compress as well as younger peats. These peats are valued more for their carbon (organic matter) content than for their physical properties (air-water relationship). They may be blended with brown peats to meet very specific requirements.

Particle size distribution is the other parameter that Lambert Peat Moss uses to describe its products in order to meet the needs of our customers. Particle size is often profiled as a series of sieve/screen retains or as the size of a screen opening that peat particles can pass through. We evaluate peats using both systems but we define them by the latter system for the various market segments. These are our descriptions:

  • Coarse Peat: Peat particles are 0 – 20 mm in size with some chunks or aggregates of peat present. Some small sticks may also be present.
  • Medium Peat: Peat particles are 0 – 10 mm in size with very few chunks or aggregates of peat present. Typically stick-free but some sticks may be present.
  • Fine Peat: Peat particles are 0 – 7 mm in size and it is free of sticks and aggregates of peat.
  • Super-Fine Peat: Peat particles are 0 – 3 mm in size and is free of sticks and peat aggregates.

Lambert Peat Moss has the flexibility to provide our customers with any grade or size of peat that they may desire for their success.