Physical Testing For Soilless Media

Porometer - $80

The porometer test standards were developed by North Carolina State University and are done in triplicate with results given as an average. This process takes longer than our other testing processes - our laboratory can only run these tests Monday - Wednesday, once the tests are run the typical turnaround time is 3 business days.  A porometer test includes the following:

Total Porosity

Percentage of total pore space in the sample

Container Capacity

Percentage of water the sample will hold against gravity

Air Space

Percentage of space in the sample that will not hold water against gravity

Bulk Density

Density of the material when completely dry (lbs./cu ft.)

Moist Bulk Density

Density of the material after draining excess water (lbs./cu ft.)

% Moisture

Moisture of the sample after soaking

Initial % Moisture

Moisture of the sample as received

Moisture - $55

Determined by loss on drying and expressed in percent. Typical turnaround time is 3 business days.


  • Media Sieve- $55
  • Dry Fertilizer Sieve- $62
  • Sieve by pan- $18

Sample is physically separated/sorted to determine various sizes of particles contained in the mix. Results are expressed as percentages of mix retained per specified sieve series. Please contact us at 1-866-522-5752 prior to submitting samples to let us know what screen sizes you require. Typical turnaround time is 3 business days. 

Instructions for Submitting Physical Samples

  1. Please specify if porometer or sieve is needed. Send at least 2 gallons of media in a plastic resealable bag. (Typically, unused media is sent.)
  2. Be sure to label each bag with a unique ID code.
  3. Include a letter stating your name, address, phone, fax, and email address. Specify the physical tests required. (If physical test is not specified, your sample will be treated as a standard nutritional media test.)
  4. Ship samples to: JR PETERS Lab, 6656 Grant Way, Allentown, PA 18106.
  5. If you have any questions, call 1-866-522-5752, ext. 46.