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The Beef with Perlite?

CorneliusSchrute

A leuco by any other name would still be as glutto
I have read for a while on various boards that many people dislike perlite as a planting media. Some of this is personal I am sure (I hate vermiculite for nary a good reason), but I am curious about why other growers dislike the aforementioned amendment.

I have had better luck with perlite than sand in my CP pots, but I only had fine grade sugar-looking silica available. This year I have found some coarser stuff to use: a bit of personal inquire, I suppose.

Your thoughts?
 
It floats and I have to order it. Thats my only problem with it. I'd actually prefer a peat/sand/perlite mix but, again, I have to order perlite.
 
Interesting: I have a pretty easy time finding perlite, but the appropriate grade of silica is a toughy for me. I have decided to hit up sand blasting services in the area tomorrow to hopefully find the good stuff.

Where do you procure your silica sand?

Also, the floating is a pain. Agreed.
 
You can find the perfect grade of silica sand anywhere that sells swimming pool supplies.
 
Home Depot usually carries the pool sand. You might have to check with several stores, some have it some don't. To a mention of vermiculite...in the south of my hometown there is a previously industrial area that has been turned into a art complex with apartments, galleries, a brewpub, bar, etc. One area there was called the silos, as it oddly enough was full of smallish storage silos, and these were rented out to artists. On that site a prior tenant was manufacturing vermiculite and had processed tons or rock that contained asbestos. Many years later is was, "Whoopsie, this area is contaminated, must be fenced off, eventually remediated" and that ended up being basically covering it up with concrete.
 
When I mix up my peat/sand/perlite/whatever mix, by the time I get to the bottom of the bucket its 50% perlite...
 
As long as I don't have it in anything that gets flooded, I like perlite. One big hassle is washing it though.
 
I am "anti-perlite", for CP-use, for four reasons:

1. newbies to the hobby sometimes think they need it, (because they read they need it)
so they get perlite with fertilizer added, because they dont know any better, and they poison their plants.

and I dont use it myself because:

2. It floats to the top.
3. It's ugly.
4. I cant think of any benefit to using it.

Scot
 
I like perlite a lot, especially in looser mixes for neps consisting of mostly LFS. Make for chunkier, airier mixes, though there are substitutes. And I've had it in my bog pot this whole summer and haven't had any floating to the surface, though in smaller pots I have seen it happen.
 
  • #10
You can find the perfect grade of silica sand anywhere that sells swimming pool supplies.

Here is where I have had limited luck. The pool filter sand I bought yesterday and hope to find more of tomorrow seems to be right. The previous filter sand I purchased from The Home Depot and Do It Best was far too fine: it looked like granulated sugar. I also can only find blasting sand of that same too-fine mesh. That fine sand is awful... it basically turns your media into concrete. I should have looked harder in the first place, I guess.
 
  • #11
Many years later is was, "Whoopsie, this area is contaminated, must be fenced off, eventually remediated" and that ended up being basically covering it up with concrete.

I hate it when that happens. ;)

Doesn't vermiculite contain other bad substances, too? Maybe my dislike for it is founded after all.
 
  • #12
I am "anti-perlite", for CP-use, for four reasons:

1. newbies to the hobby sometimes think they need it, (because they read they need it)
so they get perlite with fertilizer added, because they dont know any better, and they poison their plants.

and I dont use it myself because:

2. It floats to the top.
3. It's ugly.
4. I cant think of any benefit to using it.

Scot

Scot does remind me of one of my perlite-peeves with this post: it seems to me that sphagnum top dressing grabs hold of peat and maybe even peat/sand better than perlite/peat. Plus, if you want to harvest the sphagnum later it is bound to have perlite in it.
 
  • #13
As long as I don't have it in anything that gets flooded, I like perlite. One big hassle is washing it though.

Fun fact: I have only ever washed perlite once. I removed a lot of powder by doing so, but felt like it was too much of a hassle for me.
 
  • #14
Add to my list the powder, oh I hate the powder :censor:.

Why has no one mentioned the powder!
 
  • #15
Powder, as I recall, was an excellent movie, however.
 
  • #16
I dislike how floaty/fly-away perlite is as well as that it can compact over time. The foamed glass that is out now is much stronger, light (but not as light as perlite), and still provides the benefits of perlite.


 
  • #17
I’ve got to stand up for the much maligned Perlite, :-D

I have never ever washed perlite before use, why is it necessary?
Perlite does float when full of air, but you get it wet, as it should be in a bog or bog plant pot, its buoyancy is very low, so low it wont overcome the weight of peat above it and float.
I contains huge amounts of water and or air.
It opens the texture of the substrate.
Light and easy to handle and measure.

I have found using it in bogs for years, that it doesn’t inhibit sphagnum growth, it also turns green when on top of the substrate so doesn’t look so unsightly after a while (and who cares anyway, put some gravel or peat over it if it offends) and if it does ‘float’ to the top, (rather than the peat for sinking, nobody blames the peat for sinking do they? Oh no! it's got to be the perlites fault hasn't it) one assumes that being so light it has the good grace to get blown off and away by the wind, although this doesn’t seem to happen, curious.

Cheers
Steve
 
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  • #18
Steve,
good defense of perlite!
but..your only benefits to the plants themselves are:

It contains huge amounts of water and or air.
It opens the texture of the substrate.

I can see how that can helpful for houseplants..but why would you want either of those things for CP's?
(im talking about mainly VFT's and Sarracenia..Perlite for Nepenthes and Pings can be (and should be) a completely different conversation.)

VFT's and Sarrs, in the wild, live in very wet peat bogs..
their roots are designed to be in contact with more water, and less air, than most plants..
yes, they dont need to be 100% saturated with water, and there is some air in the peat and sphagnum,
but why would you need perlite to *increase* the amount of air in the mix?
the plants dont want or need increased air in the mix..

If sphagnum and peat is what the plants grow in, in the wild, then it seems to me that sphagnum and peat
in the ideal media to grow them in, in captivity..
(I also dont like sand in VFT and Sarr mixes, for the same reasons..if they dont grow in sand in the wild (which they dont)
why should I add sand to my mix? again, I see no benefit or reason for it..)

so it comes down to..what is the benefit to using perlite for VFT's and Sarrs?
I see zero benefit, or need, or use, for perlite..
perhaps using it (if its clean) is "neutral"..no gain, but no harm..
but if that is the case, why use it at all?

I think perlite use for VFT's and Sarrs is a "myth" that hasn't quite died out yet..
people still use it just because they think they should..just because they read it somewhere..
it probably came over from the houseplant world: "perlite is good, you want it in your mix, period."
but does it offer any *real* benefit for "bog" CP's?
IMO, no, it does not..

Scot
 
  • #19
I've used mortar/concrete sand (used in construction), for many years.
It's the perfect grade, course, construction grade, heavy, course sand, mixed with tiny pebbles.
The sand comes in 25 lb bags for about $5.00.
You can only find it in the lumber/builders dept. at LOWES!
 
  • #20
There's nothing wrong with Perlite as a soil component as long as you are using it wisely, and in the right context.

1) As others have pointed out, there's no need to use Perlite in soil mixes for North American terrestrial CPs like Sarracenia, since it doesn't bring anything beneficial to the equation; sand and peat are the two components that are much more suitable for Sarracenia/Dionaea. Perlite is more useful in a Nepenthes media formulation, where the coarse chunks help make a very airy, fast draining media. If you want ideal sand for Sarracenia, go to a building supply place and request Pool Filter sand; that is what I use.

2) Perlite contains fluoride, and it does leach out of the perlite over time, so it is best to limit how much perlite you include in a mix, just to err on the safe side of avoiding fluoride toxicity. IE: no more than 30% perlite by volume.

Otherwise, there is no reason to avoid using perlite, unless you simply cannot tolerate its physical properties because they offend your sensibilities. Oh, and about perlite dust: it is basically powdered glass, and is therefore capable of contributing to silicosis of the lungs if inhaled, so at least wet it before you handle it! I buy fairly large bags of it and the first thing I do is cut off the top of the bag and pour copious amounts of water into the bag (not before poking a couple of small drainage holes in the bottom), allow it to drain, and repeat once more. Never handle the stuff when its bone dry.
 
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