Washed vs High EC Cocopeat: Which Grade for Your Crop?
The most important number on a cocopeat spec sheet is EC: electrical conductivity, a measure of the salts in the pith. Coconuts grow near the coast, so raw coir pith carries natural sodium and potassium salts. How much of that is removed decides the grade, the price and what you can grow in it.
High EC (natural) cocopeat
High EC cocopeat is natural, unwashed coir pith. It is the cheapest grade because it skips washing and the extra drying that follows. It is a good choice for soil amendment, landscaping, bedding, and for blenders who wash or buffer the pith themselves.
Washed cocopeat
Washed cocopeat is rinsed in fresh water to flush out salts, typically reaching about 0.5–0.7 mS/cm. It is the standard grade for greenhouse grow bags, nurseries and potting mixes. Our washed grade was tested by the Coir Board's research institute at EC 0.64 mS/cm.
Buffered cocopeat
Buffered cocopeat is treated, usually with a calcium solution, so that sodium and potassium held on the pith are displaced and washed out, bringing EC below 0.5 mS/cm. It costs the most and suits very salt-sensitive crops and strict soilless systems. Because results vary by lot, ask for a lot test before you buy.
Quick guide
| Use | Grade |
|---|---|
| Greenhouse vegetables in grow bags | Washed |
| Nursery and seedling trays | Washed (Buffered for very sensitive crops) |
| Potting mixes | Washed, or High EC if you wash it yourself |
| Soil amendment, landscaping, bedding | High EC |
Price follows EC
Each step down in EC adds washing, drying or buffering, so lower EC costs more. Buy the grade your crop actually needs rather than the lowest number on offer.
Frequently asked questions
Not exactly. Many suppliers call washed cocopeat at 0.5-0.7 mS/cm low EC; others reserve the term for EC below 0.5. Always ask for the number.
Yes, by washing it in fresh water and checking the runoff EC. Buffering with a calcium solution goes further.
No. EC is a property of the pith; it is measured before pressing and does not change in a dry, sealed block.