01 · Direct answer
A coir pith COA lists the values measured on a lot and the method used for each one. The usual parameters are electrical conductivity (EC) and pH in a 1:5 extract, moisture with its basis, bulk density and particle size. Check the method before the number, and then compare the number with the limit written in your contract.
| Parameter | Method to look for | How to read it |
|---|---|---|
| EC | 1:5 extraction by volume, calibrated conductivity meter | Compare with the contract ceiling for the grade bought |
| pH | 1:5 extraction by volume, calibrated pH meter | Literature for raw dry husk: 4.9-6.0[1] |
| Moisture | Weighing before and after drying | Check whether the basis is wet or dry |
| Bulk density | Mass divided by volume in a graduated container | Sets the weight of a 100 L bag |
| Particle size | Screening or visual conformity with a stated screen | Very fine particles clog aeration pores[2] |
02 · How to read each number
- EC (1:5). Check the extract ratio first, because 1:5 and 1:1.5 give different readings of the same material. Raw husk ranges from 0.4 to 6.0 mS/cm according to EMBRAPA, so the value of the lot is what counts.[1] Bands by crop are in Coir pith EC by crop.
- pH (1:5). The literature for raw dry coconut husk runs from 4.9 to 6.0, and the grower corrects pH in the formulation or the fertigation.[1]
- Moisture. Wet-basis and dry-basis figures differ on the same lot, so the basis has to be on the certificate.
- Bulk density. Multiply by 0.1 to get the weight of a 100 L bag. Conversion to liters per kg is in Coir pith liters per kg.
- Particle size. Particles below 0.5 mm are undesirable because they clog aeration pores.[2]
03 · What a COA does not cover
The conductivity meter reads the salts dissolved in the extract. The potassium and sodium held in coir's organic complex do not show in the reading, and only calcium or magnesium displaces them, according to Romero.[2] A low EC does not replace the right grade, which is explained in our guide to buffered coco coir. Tannin, organic matter, water holding capacity and minerals need a separate laboratory panel.
We sell Natural coir pith as a coir pith supplier, and each value in our specification is stated with its test method. Grades: Natural (unwashed, no additives), from our plant in Paraipaba, Ceará. Buyers who need a lower EC wash or buffer the pith at their end. Tell us your crop, your EC method and target, your volume per month and your port.
04 · Frequently asked questions
What does EC 1:5 mean on a coir pith certificate?
It means electrical conductivity was measured in an extract of one part substrate to five parts water, by volume. The ratio is part of the result, because a 1:1.5 extract gives different numbers for the same material.
Does a low EC on the certificate mean the coir pith is salt-free?
No. The conductivity meter measures the salts dissolved in the extract, and the potassium and sodium held in coir's organic complex do not show in the reading. According to Adalberto Romero, only calcium or magnesium displaces them, so for salt-sensitive crops the grade matters as much as the EC number.
Should the moisture value say wet or dry basis?
Yes. Wet-basis and dry-basis figures differ on the same lot, so ask for the basis together with the method.
Does a COA include tannin and organic matter?
Usually not. Tannin, organic matter, water holding capacity and minerals need a separate laboratory panel, so ask for it when your crop needs it.
05 · Sources
- EMBRAPA Tabuleiros Costeiros, Comunicado Técnico 226 (COT-226-19): raw EC 0.4-6.0 mS/cm and pH 4.9-6.0 of dry coconut husk.
- Ing. Adalberto Romero webinar (Science Fetti / El Semillero, Colombia, 2025): particles below 0.5 mm undesirable; water does not displace Na/K from the organic complex, only Ca or Mg.