Pumice vs perlite

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Spikylover
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Pumice vs perlite

Post by Spikylover »

As we all are moving to more mineral mixes, the prevalent opunion seems to be to use pumice. However, perlite is much cheaper and more readily available in large qunatities. If weight is the issue with perlite, you can mix it with decomposed granite or any gravel. So what's the advantage of pumice over perlite that makes it worth the added price?

Thanks.
Rachel
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ElieEstephane
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Re: Pumice vs perlite

Post by ElieEstephane »

I think perlite dust is toxic if inhaled
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teo
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Re: Pumice vs perlite

Post by teo »

I can't find any info that it is toxic - see here: https://www.ncbi.nlm.nih.gov/pubmed/24601903
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ElieEstephane
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Re: Pumice vs perlite

Post by ElieEstephane »

teo wrote:I can't find any info that it is toxic - see here: https://www.ncbi.nlm.nih.gov/pubmed/24601903
It's not toxic per se but long term exposure to silica powders will cause inflammation and swelling of lung tracts which will block respiration eventually. In the short term, it can be very irritating to people with asthma and similar diseases. When handling any silica powder at work, respiratory safety is a must.
i am only referring to perlite dust
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toson
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Re: Pumice vs perlite

Post by toson »

perlite dissolved by watering
Ron43
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Re: Pumice vs perlite

Post by Ron43 »

toson wrote:perlite dissolved by watering
Wrong. I've used perlite for longer than I can remember and it's never dissolved by water. Vermiculite will squash down, but never dissolve either. If your "Perlite" is dissolving, then somebody sold you something that is not true perlite.
williamsii823
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Re: Pumice vs perlite

Post by williamsii823 »

We wash perlite to minimize the dust. It should always be moistened when using.
Pumice is favored by many because it is more porous than perlite. It has tiny little air pockets on it's surface. A way to add air or moisture to a mix. Also, something for root hairs to grab as they grow.
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TimN
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Re: Pumice vs perlite

Post by TimN »

I use a product called TurfaceMVP which is a calcined clay product. It's similar to the clay oil-absorbent found in auto parts stores or clay cat litter. I get Turface at my local irrigation supply store (their website will help you locate a local dealer). I pay about $17 (US) for 50 lbs. Turface is also a nice tan color that blends in better than white or gray material materials.

Turface doesn't float (like Perlite or pumice), and doesn't break down over time.

I have no interest, financial or otherwise in Turface, I'm just a long-time satisfied customer.

I use Turface and coir (Coconut fiber) in an approximately 50/50 ratio for all of my cactus. I add some alkaline material for cactus that really love/need alkaline soil. Coir is somewhat acidic, but with the alkalinity of the local water it doesn't stay that way for long.

Trivia - TurfaceMVP is used for sports fields; the infield of baseball fields, if you've been to a college or pro baseball game you've seen Turface.
Disclaimer: I'm in sunny Arizona, so any advice I give may not apply in your circumstances.

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Spikylover
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Re: Pumice vs perlite

Post by Spikylover »

[quote="williamsii823"Pumice is favored by many because it is more porous than perlite. It has tiny little air pockets on it's surface. A way to add air or moisture to a mix. Also, something for root hairs to grab as they grow.[/quote]
Is that enough advantage to offset the very high price?
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TimN
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Re: Pumice vs perlite

Post by TimN »

One other thing:

Perlite - volcanic glass heated to puff it up. It's essentially porous balls of glass. -manmade
Vermiculite - mica heated to puff it up. Mica is decomposes into clay. Like mica, vermiculite is not very durable and will break down over time into clay. -manmade
Pumice - Can be similar to perlite, but volcano chemistry is variable. -naturally occuring

The information I've found on perlite and vermiculite is somewhat inconsistent and incomplete.
Disclaimer: I'm in sunny Arizona, so any advice I give may not apply in your circumstances.

Tim
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Spikylover
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Re: Pumice vs perlite

Post by Spikylover »

TimN wrote:I use a product called TurfaceMVP which is a calcined clay product. It's similar to the clay oil-absorbent found in auto parts stores or clay cat litter. I get Turface at my local irrigation supply store (their website will help you locate a local dealer). I pay about $17 (US) for 50 lbs. Turface is also a nice tan color that blends in better than white or gray material materials.

Turface doesn't float (like Perlite or pumice), and doesn't break down over time.

I have no interest, financial or otherwise in Turface, I'm just a long-time satisfied customer.

I use Turface and coir (Coconut fiber) in an approximately 50/50 ratio for all of my cactus. I add some alkaline material for cactus that really love/need alkaline soil. Coir is somewhat acidic, but with the alkalinity of the local water it doesn't stay that way for long.

Trivia - TurfaceMVP is used for sports fields; the infield of baseball fields, if you've been to a college or pro baseball game you've seen Turface.
It was my first option but i can't seem to find it locally. I did find some but they are very large (.5")and used as surface dressing. Abd the only cat litter i can find is crushed limestone.
For now i make due with a mix of 60-70% of crushed rocks and the rest is compost and some soil. I'm having amazing results! But I was looking into perlite to mix with the crushed rocks to loosen up the mix a little.
Rachel
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williamsii823
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Re: Pumice vs perlite

Post by williamsii823 »

Depends on how important is it for hat you want to grow. I buy mine from ebay ("Horticultural Pumice"), and it's not very expensive. And then use it just when needed.
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Re: Pumice vs perlite

Post by esp_imaging »

Pumice price and availability varies a lot depending upon your location.
Similarly granite. Plus the shipping cost is relatively high.
Hence if your local geology doesn't provide either, alternatives such as perlite or fired clay cat litter become a lot more attractive.
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Re: Pumice vs perlite

Post by esp_imaging »

TimN wrote: Vermiculite - mica heated to puff it up. Mica is decomposes into clay. Like mica, vermiculite is not very durable and will break down over time into clay.
Really?
For sure, vermiculite breaks down into individual tiny sheets of mica, but I thought mica was very chemically stable.
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DaveW
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Re: Pumice vs perlite

Post by DaveW »

This Bosai site, where our hobby originally pinched the idea from, usually keeps up to date with any sources of suitable cat litter or it's substitutes in your country if you scroll through the pages. Make sure you get the correct type of cat litter, as all cat litters are not the same. In the UK Tesco Supermarkets mentioned keeps three types of cat litter ranging in price from the cheapest to it's premium one. The cheapest is made from shredded paper, the next is white coloured and from something like Fullers Earth, which goes mushy when wetted and the one we use the Premium Low Dust stuff which is red fired granules. Other supermarkets and pet stores may stock different, but sometimes unsuitable cat litters for our use. The oil absorbers sold for garage use to soak up oil spills also vary like cat litters in what they are made from, so again be sure you get the correct type.

http://www.bonsai4me.co.uk/Basics/Basicscatlitter.htm

As said by a previous poster, your national EBAY is always a good place to look for anything you cannot find locally. I got some pumice off EBAY, but it is not cheap in the UK since we have no natural source, so it's all imported. Very few potting ingredients are cheap if they are delivered in small packs due to their weight to transport. Cheapest is always from a local supplier if you can find one where you collect them yourself, since they buy in bulk, therefore their transport costs are cheaper per bag.

For crushed granite chips I get them from my local builders merchant, since the Building Trade used them in concrete for steps etc and they are a lot cheaper than they would be from a horticultural supplier. They were sold as 1/4 inch to dust (or now the metric equivalent) but you will need a fine screen or sieve, about the same mesh size as fly screen or a flour sifter, to sieve the small amount of dust out since it tends to clog. The ones I bought were in the same pack size as the limestone chips below.

Limestone chippings are also probably cheaper from your local builders merchants. Make sure they are the size you want though since often several sizes are stocked, some too large for our use. Unlike the ones in the link below I think mine were only about 10mm in size. However whether you really need limestone chips for cacti is debatable.:-

https://www.travisperkins.co.uk/Limesto ... k/p/996263
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