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Noob question on perlite vs vermiculite. Question about expanded shale added

MeatHead1313

MeatHead1313

Hi all. As a still fairly new grower, I've done a lot of chopping and changing of my mixes to try to find the right one. As it stands, I have some plants in basic Miracle Gro potting mix, which I find to be way too heavy without additional aeration added, some in Fox Farms Ocean Forest, which I'm loving but is far too expensive as I have to order it online, and some in a homemade mix which seems to be doing quite well, and the ingredients are cheap until it comes to the perlite. Unfortunately all I can find around me locally is Miracle Gro perlite in the 8 quart bags, which seem to be ridiculously over priced. The problem is, to order non fertilized perlite in larger bags online ends up costing me around $30-40 a bag, which makes the MG perlite look good. I can get 1.5-2cu ft bags of vermiculite cheap locally, and was wondering if this would be a good substitute for the perlite in my potting mix? I'm growing strictly in containers, with most being either root pouches or dollar store eco friendly bags, with some pots or 5 gallon buckets. It's extremely humid here in summer, and tends to be fairly wet as well. Would the vermiculite hold too much water for my conditions? My standard mix is 1/3 peat, 1/3 compost/worm castings/manure, ad 1/3 perlite. 
 
They do not work the same way at all, unfortunately. 
 
Vermiculite soaks up water like a sponge and holds it, releasing it slowly. Perlite does`t soak up water and provides a lighter, more airy mix. Vermiculite compacts like crazy in pots, whereas perlite works the opposite way and keeps the soil from compacting. There are a lot of very useful applications of vermiculite. This isn`t one of them.

Pumice is a good substitute for perlite.

Another one is Lava rock

Oh, and smashed up stryofoam would also be Ok (polystyrene in the rest of the world).
 
Nigel said:
They do not work the same way at all, unfortunately. 
 
Vermiculite soaks up water like a sponge and holds it, releasing it slowly. Perlite does`t soak up water and provides a lighter, more airy mix. Vermiculite compacts like crazy in pots, whereas perlite works the opposite way and keeps the soil from compacting. There are a lot of very useful applications of vermiculite. This isn`t one of them.

Pumice is a good substitute for perlite.

Another one is Lava rock

Oh, and smashed up stryofoam would also be Ok (polystyrene in the rest of the world).
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Thanks Nigel. I had a feeling this was the answer I would get. Guess I was holding out hope that the local Lowe's had some idea that they knew what they were doing by stocking big bags of vermiculite instead of perlite here. Trying another relatively local feed store tomorrow hoping they'll have what I want. 
Where would be a good place to look for pumice or lava rock? Online prices for everything are great until shipping is factored in. 
thirdcoasttx said:
Meathead where are you at? Here in south texas our local nurseries have perlite super cheap.
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Lafayette Louisiana. The best I can find here is 8 quart bags for the perlite. Local nurseries have non MG bags, but want roughly $10 a bag, which makes the MG bags from Lowes seem good. Trying to avoid MG products, as I've been finding my plants in them are a magnet for fungus gnats and aphids. while my other plants aren't affected as bad.
 
hogleg said:
Rice hulls work well to make a dense soil fluffy. Cheap and available at most feed stores.
Just a thought.
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Will look out for them in the morning. Hitting a few feed stores I haven't checked yet to see what they have.Appreciate the info. Do the rice hulls hold up well over a season or 2 though?
 
OKGrowin said:
you should be able to find perlite~3cuft for 20$, i had to call local nurseries as they don't sell it at walmart,lowes,depot
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All the local nurseries I've checked only carry the 8 quart bags for some reason, and unless it's Miracle Gro they all want around $10 a bag. 
 
After seeing your updated grow list it looks like you will need quite a bit!! Our local nursery sells 8 quart bags for like 4 bucks a bag. They hydro store has massive bags but im not sure how much they run.
 
Thanks guys. Checked the feed store today and no luck. Only  small bags of perlite, big bags of vermiculite and no rice hulls. They did have expanded shale though. Does anyone have any info on using the shale instead?
 
hogleg said:
I'm not familar with ex shale. After looking it up it looks a little heavy and sounds like it holds a lot of water. But i have not used it.
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It is heavier than perlite, which I believe could be an advantage over perlite as it won't float like perlite does. The water retention is what I'm worried about, and hoping to find info on as we can get quite a bit of rain down here during summer.
 
XLNT said:
Meathead,  
 
This place looks pretty close to you-  http://www.ourcrazydeals.com/hydroponics.html
 
A lot of concrete construction companies also frequently use perlite.  
 
Maybe a couple of quick calls to your local masonry supply companies might be fruitful.
 
Martin
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Thanks for the info. Youngsville's only about a 10 minute drive from me and I never knew that place was there. It's never shown up for me during any searches I've made. Just checked the site but it seems they don't have perlite though.
Huh. Didn't know perlite was used in concrete construction either. May have to find some local companies and give them a call. Appreciate it!
 
Leaves work great as well but you need a lot of them and it takes quite some time for them to break down.
jerrywastheman said:
I'm using the big bags from HD this year : http://www.homedepot.com/p/THERMOROCK-2-cu-ft-Perlite-489701/202187623
 
They also have vermiculite:  http://www.homedepot.com/p/THERMOROCK-2-cu-ft-Medium-Grade-Vermiculite-489702/202187625
 
Good luck!
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I use that as well in smaller pots but what I hate is that a good portion of the bag contents have been crushed to almost powder. :( I wish it was twice as big as it is and had no small fines in it. I am using 5/16" red lava rock that I bought from a landscape supplier here in my area. They sell it by bags you fill yourself or by the yard or half yard which I purchased. Red lava rock does make the container heavier but I think it is far better overall as it also is a source of basalt rock in your soil so you get the benefit of minerals that you won't get from anything other than rock dust which I also put in the container at 4 cups per cubic foot of soil.
 
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