Perlite | 100g
Typically formed by the hydration of obsidian, perlite is a naturally occurring, non-renewable volcanic glass with a relatively high water content. It’s currently mainly mined from Armenia, China, Greece, Hungary, Turkey and the USA. Unusually, perlite expands exponentially when heated sufficiently. This and other factors (such as its low density once processed) make it a valuable horticultural, commercial and industrial mineral.
In the garden or greenhouse, perlite is an invaluable non-organic medium for rooting cuttings, as well as for mixing in with soil and other potting ingredients to produce a nicely aerated, well-draining mix in which to grow your precious plants. It’s also a useful tool when delving into the world of hydroponic growing or mycology growing too!
Non-toxic, stable and resistant to microbial attacks and other travails, perlite is quite versatile, often being substituted for materials such as diatomaceous earth (especially for filtration), expanded clay (as lightweight filler for building materials), pumice (to improve soil drainage), shale and vermiculite (although vermiculite retains much more moisture than does perlite).
Treated perlite typically comprises of roughly 70–75% silicon dioxide, 12–15% aluminium oxide, 3–4% sodium oxide, 3–5% potassium oxide, 0.5-2% iron oxide, 0.2–0.7% magnesium oxide and 0.5–1.5% calcium oxide. While perlite is pretty much non-toxic, needless to say that we don’t recommend breathing in any fine, powdery materials if you don’t have to – wear a breathing mask and goggles when working with such things!
Essential for good drainage in potting mixes – especially for cacti and succulents! | Ships from Spain