Vermiculite is the name of a group of hydrated laminar minerals (aluminum-iron magnesium silicates) which look like mica. Horticultural vermiculite is processed with massive heat that expands it into accordion shaped pellets composed of multiple layers of thin plates. It will not rot, deteriorate, or mold and is enduring, odorless, non-toxic, and sterile.
A hydrous, silicate mineral which has the following benefits:
- Inorganic, inert and sterile
- Ultra light weight
- Free from disease, weeds and insects
- Slightly alkaline (which can neutralized with the use of peat)
- High cat-ion exchange (or buffering exchange)
- Excellent aeration characteristics
- High water holding capacity
For the horticultural industry and home gardens it is ideal for use in the following:
Combined with other materials such as peat or composted pine bark to produce soil-less growing media. These mixes promote faster root growth and help retain moisture, air, and nutrients, releasing them as the plant requires them.
Can be used alone or mixed with soil or peat to germinate seeds. Very little watering is required. When used alone, seedlings should be fed with a weak fertilizer solution when the first leaves appear.
For heavy or sticky soils, the addition and mixing in of vermiculite up to one-half the volume of the soil is recommended, as a soil conditioner. This creates air channels, allowing the soil mix to breathe and provides the necessary air to maintain vigorous plant growth.
Where soils are sandy, mixing vermiculite into the soil, allows the soil to hold the water and air needed for good growth.