Agriperlite 3/5 mm - 2 lt pack

What it is and where it comes from

Agriperlite comes from a siliceous rock of volcanic origin which, brought to high temperature, expands and swells until it becomes the white, extremely light granule you see in the photo. It is a natural inert material. The expansion process makes it sterile and inorganic, therefore free of fungal and bacterial load.

This pack contains agriperlite with a 3/5 mm grain size, in a 2 litre format.

How it behaves in the pot

The granule is full of closed micro cavities: it holds water on the surface and in the outer cells, but it does not soak through like an organic sponge and lets the rest drain away. The result in the pot is a substrate that stays open, where air reaches even the deepest roots and waterlogging struggles to form, even after long spells of rain.

It does not break down into clay. The agriperlite granule withstands the season and the years between one repotting and the next without closing up, and this is what sets it apart from organic materials that collapse. One limit should be mentioned: being very light, a mix with too much agriperlite tends to float to the surface when watered with a strong jet and gives little stability for anchorage. For this reason, on already established plants, it is happily paired with heavier materials such as pumice or akadama.

Features

• Type of material: natural inert of expanded silica
• Grain size: 3/5 mm
• Pack capacity: 2 litres
• Sterile and inorganic: does not encourage fungi and bacteria
• Function: drainage, aeration, water retention

Which grain size and for which plants

The 3/5 mm is a medium size, handy for medium-sized pots and for bonsai in training. On shohin and shallow pots it is used sparingly, because the pale granule remains clearly visible on the surface. The 2 litre pack is a modest format, suited to those repotting just a few plants or wanting to try the material without committing to larger quantities. It has no species preference: being inert and neutral, it pairs with broadleaves and conifers without altering the character of the mix, and it is also used on acid-loving plants alongside kanuma, which remains the reference material for azaleas, camellias and rhododendrons.

The use where agriperlite really shines, however, is another one: propagation. As the sole component of the substrate it is excellent for rooting cuttings and for transplanting plants lifted from open ground, where a clean, airy and constantly moist environment is needed without being soggy: 2 litres are enough to fill a few cutting pots.

How to use it when repotting

First of all, the dust. Agriperlite produces quite a lot of it during transport and it should be sieved out, ideally with the material slightly dampened: you avoid breathing it in and the final mix drains better. Two passes through the sieve are enough.

A drainage layer can be spread on the bottom of the pot, then you proceed with the body of the substrate, working it between the roots with a chopstick, without compacting. For the first watering it is best to use a fine rose and not a direct jet: the white granules, light as they are, would be washed to the surface. After a few waterings the substrate settles and the problem does not come back.

Frequently asked questions

Can agriperlite be used on its own?

Yes. By itself it works well as a substrate for rooting cuttings and for transplants from open ground, where having a sterile, airy medium is what matters. On bonsai already in pots it is preferable to pair it with heavier materials, which give stability to the root system.

Does the granule break down over time?

No, it is an expanded siliceous inert and does not degrade like an organic component. It does not turn to paste or become suffocating clay between one repotting and the next. The only care needed is mechanical: strong pressure with the fingers can crush the granules, so settle it with a chopstick without squashing.

Why is it said to prevent fungi and bacteria?

Because expansion at high temperature makes the material sterile and because, being inorganic, it offers no matter to decompose. It is not a fungicide: it will not cure rot that is already present. It simply does not provide the ground on which colonies take hold, which helps a great deal with cuttings.

What is included

• Agriperlite, 3/5 mm grain size
• 2 litre pack

Those who prefer to measure out the components themselves can put together their own mix on the custom soil mix page.