Vermiculite is a hydrous phyllosilicate mineral. It undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently, and the effect is routinely produced in commercial furnaces. Vermiculite is formed by weathering or hydrothermal alteration of biotite or phlogopite.
I would use perlite in potting compost to improve drainage.
I would use vermiculate on top of the compost after sowing seeds in seedtrays for seeds that need light to germinate, as it allows light through but stops the seeds from drying out.
I tend not to buy either, and use horticultural grit for both purposes as I don't have room to store everything in my little shed.
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
What Dove says. Watch out with perlite, you need to thoroughly wet it in the bag before using as the dust can be very easily breathed in.
Not keen on Vermiculite as I find it is too light and blows away on the pots of outdoor sown seeds and it does allow the growth of mosses and liverwort too.
I bought a bag of Perlite, thought I'd try it, it was cheap from Amazon, I didn't think of it being so light, when it arrived the bag was almost as tall as me. I tried it on top of seeds but don't like it, so wil mix it in the compost. I have enough to last a life time.
Gardening on the wild, windy west side of Dartmoor.
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Vermiculite is a hydrous phyllosilicate mineral. It undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently, and the effect is routinely produced in commercial furnaces. Vermiculite is formed by weathering or hydrothermal alteration of biotite or phlogopite.
Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian.
So Vermiculite is a shaped like flat plates and Perlite is little balls.
Both hold water, but in a different way. Perlite soaks it up, but Vermiculite holds it between the plates.
Both are chemically inert so they have no effect on the pH of the compost.
Thanks Berghill. You know your stuff!
In very simple terms (for my small brain) how should they be used differently in gardening, or do they do the same thing?
i ask because both are on offer in Aldi!
I would use perlite in potting compost to improve drainage.
I would use vermiculate on top of the compost after sowing seeds in seedtrays for seeds that need light to germinate, as it allows light through but stops the seeds from drying out.
I tend not to buy either, and use horticultural grit for both purposes as I don't have room to store everything in my little shed.
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
What Dove says. Watch out with perlite, you need to thoroughly wet it in the bag before using as the dust can be very easily breathed in.
Not keen on Vermiculite as I find it is too light and blows away on the pots of outdoor sown seeds and it does allow the growth of mosses and liverwort too.
I bought a bag of Perlite, thought I'd try it, it was cheap from Amazon, I didn't think of it being so light, when it arrived the bag was almost as tall as me. I tried it on top of seeds but don't like it, so wil mix it in the compost. I have enough to last a life time.