Cocopeat and Perlite Mix: Specify Your Blend

Why add perlite to cocopeat?

Perlite is used in horticultural blends to influence aeration. The Perlite Institute describes how perlite particle size changes air space after drainage. That makes the grade part of the specification, alongside the amount added.

There is no single ratio that this guide can prescribe for every crop and container. A blend should be evaluated with your irrigation, container dimensions and production routine. The percentage of perlite is also not a direct statement of the finished medium’s measured air-filled porosity.

Before asking for a blend, describe the current issue precisely: difficult filling, slow drainage, variable wetting or a need to match an existing product. These observations are more useful than asking for the “best” cocopeat mix without an application.

Write the ratio with its measurement basis

Specify whether proportions are by loose volume or by mass. These are different instructions. A recipe described as 70:30 by volume means measuring 70 volume units of prepared coir and 30 of perlite under an agreed procedure; it does not mean weighing 70 kg and 30 kg.

Record how the coir was hydrated and loosened, how each component was measured and whether the measuring container was pressed or shaken. Repeat the same preparation when comparing another sample.

Include these details in a blend request

Ask whether the quoted blend is the same as the supplied trial sample. If a component or ratio changes, request a new sample code and revised specification. This creates a clear reference for later orders.

Run a small, recorded comparison

Use your current medium as a reference and compare it with a limited number of candidate blends. Fill identical containers consistently. Iowa State Extension notes that pressing or tapping media can reduce air space, so filling technique should be controlled during the comparison.

Record irrigation settings, water applied, drainage observations, settling and root development. Photograph labelled containers from the same angle on each review date. Record labour and handling observations as well as crop observations.

Set the decision criteria before the trial starts. For example, you may want consistent filling and predictable drainage under a documented irrigation routine. Do not infer a yield improvement from a short handling trial. Discuss the observations with your crop adviser before scaling up.

Teral’s loose-media range includes a cocopeat-with-perlite option. Use the 50 L bag comparison to distinguish that format from low EC and buffered coir.