Any of a group of micaceous hydrated silicate minerals related to the chlorites and used in heat-expanded form as insulation and as a planting medium. (noun)
Examples of word vermiculite
The name vermiculite was created from the Latin word for worm, vermiculus.
This year it is to be micro-plants, grown in vermiculite.
I need some stuff called vermiculite to condition the soil so that the roots grow well.
Some lightweight mineral and rock materials, such as vermiculite, diatomite and perlite are similar to micas and can be used in place of mica.
If seeds must be shipped over long distances, it may be possible to prolong viability somewhat by packing them in a moist, well-aerated medium, such as vermiculite or sawdust, in a perforated plastic bag inside an air-porous bag.