LESS PERLITE = BETTER?

[michael68]

Hi there, been reading about soil mixes and such, and Mandala seed company and a few other sources seem to think less perlite is better. I've read a lot of threads on forums with people using like 20% perlite and stuff.

http://www.mandalaseeds.com/Guides/Soil-Guide

"Photo: an example of quality potting soil - the texture is fluffy & soft, made from fine-grade sphagnum peat, the white specks are traces of perlite. Notice how little perlite professional potting soil contains (1% of total volume)! One of the most common mistakes growers make is to ruin their soil mix with high amounts of perlite."

"Adding a large amount of perlite/vermiculite (some growers add as much as 25%!) is a completely outdated practice from 30-40 years ago when there was only a very small selection of horticultural potting soil available for non-commercial gardeners. It is one of the unfortunate harmful practices in cannabis cultivation that many still cling to although they do not understand the reason or consequences. "


Thoughts?...

 

[Hammerhead]

you dont want to put so much in that the nutrients just drain right off. If you get the mix right you will be fine.. I use it all the time for various growing needs.

 

[LastWaltz]

It really depends on how often you are willing to water. I know people have used 100% perlite and just watered every day with a organic nutrient tea. And I love Mandala genetics but pro-mix works just fine and they have it under "Brands to Avoid".

100% Perlite hard to argue its anything more than personal preference

 

[michael68]

Cheers but I've read so many soil mixes and stuff that use like 20% +, so is a smaller amount like below 10% percent better? Even 1%?

 

[Hammerhead]

You dont have to use perlite you can use any substrate that allows for good drainage. The only medium I hate is vermiculite IMO theres no use for it in horticulture.

I have seen many use 50/50 Perlite COCO. What ever is used has to make for good drainage

 

[softyellowlight]

hahahaha 1%, like that does ANYTHING!

 

[gOurd^jr.]

I've recently acquired some biochar from a nearby company that produces portable charring ovens. It has a very, very similar texture and effect on the soil mix as perlite. very light and fluffy, you can crush it into powder easier than perlite but is holding chunkiness fine unless crushed. Seems it has much more water holding capacity than perlite. Also it has more reactivity i.e. very high cation exchange capacity (can suck nutes out of soil for a while) and a high PH, which buffers both the peat I've quit using and the Manure I now have in a huge pile out back...
It's been used for thousands of years if you haven't read the sticky on Terra Pretta check it.
WAAAYYY better for earth than perlite factory...and virtually identical in texture. can be homemade too.
Yes I think less=Better

Aeration and drainage you can't really get enough of if your willing to water a lot. I just think it can be gotten better without perlite.

 

[TACOE]

Based on years of agricultural research on potting soil. (by universities) I use 25-30%. Why mess with a system that works. We are talking about ORGANIC SOIL are we not? We are also talking about container gardening I assume. If you are experimenting with methods that are not related to traditional or typical organic container ag, then go for the 100% But I'm thinking this is the wring forum for that.
If you are going for any sort of organic soil I would not use less than 20%. It may work. But imagine how well it would work if u built soil correctly

Or we could just ignore empirical research

Btw perlite is no longer something I mess with. It holds no water. And it certainly holds no nutes

 

[michael68]

I live in a dry climate but I still don't want soil compaction.

How would this be?

40% peat moss
40% compost (probably mushroom or just regular garden compost)
10% perlite
10% manure

and of course dolomite and some added meals maybe.

 

[michael68]

And if perlite is no good what do you use for your aeration amendment, etc? Pumice?

 

[Hammerhead]

Or just buy a few bags of FF light Warrior

 

[michael68]

Or just buy a few bags of FF light Warrior

I'm trying to build a soil from scratch, I'll probably end up going with something more common though too along with it.

 

[TACOE]

I live in a dry climate but I still don't want soil compaction.

How would this be?

40% peat moss
40% compost (probably mushroom or just regular garden compost)
10% perlite
10% manure

and of course dolomite and some added meals maybe.

Is this outdoors or in?
Since it's dry. Just water more often. Soil structure is very important. More than just holding water. So I wouldn't cut perlite just cas of that

If it's outdoors. Then idk. If ur not using native soil you will probably need more perlite. What kinda manure? If it's chicken that's prolly too much. If it's sheep cow or horse. Make sure it's composted. Then just include that in the compost blend

I'm getting the feeling this is outdoor. So others will be more help.

Oh and I use rice hulls + de

But yeah. Overall if it's peat based. I would say you NEED more perlite. But I only do things the way I do em. Cant say for sure what won't work

 

[Booyah!]

Outdoor you'd want more water retention than inside

 

[Hammerhead]

I'm trying to build a soil from scratch, I'll probably end up going with something more common though too along with it.

I use to make my own it just became to much of a hasel. You need to have all the amendments to add to your mix.

Mine was

sunshine mix#2 lime,worm castings,Bat Guano,perlite,Blood Meal. Sometimes I would add a bag or 2 of Light Warrier to this.

 

[TACOE]

I've recently acquired some biochar from a nearby company that produces portable charring ovens. It has a very, very similar texture and effect on the soil mix as perlite. very light and fluffy, you can crush it into powder easier than perlite but is holding chunkiness fine unless crushed. Seems it has much more water holding capacity than perlite. Also it has more reactivity i.e. very high cation exchange capacity (can suck nutes out of soil for a while) and a high PH, which buffers both the peat I've quit using and the Manure I now have in a huge pile out back...
It's been used for thousands of years if you haven't read the sticky on Terra Pretta check it.
WAAAYYY better for earth than perlite factory...and virtually identical in texture. can be homemade too.
Yes I think less=Better

Aeration and drainage you can't really get enough of if your willing to water a lot. I just think it can be gotten better without perlite.

You are using something for drainage/aeration right? I don't believe that char is to replace perlite. I would compost it first. And being better for the earth - assuming u are charring waste products, then I suppose it's ok. I still don't love the idea. But I did read an interesting article on biochar in April issue of acres

If the topic title is intact asking what I interpret: "is less than 20% perlite in a peat moss mix better than more?"
I would still say absolutely 100% not

 

[mad librettist]

reposted, from AL on gardenweb.

An illustrative question: How much perlite do we need to add to pudding to make it drain well?

I already stated I hold as true that the grower's soil choice when establishing a planting for the long term is the most important decision he/she will make. There is no question that the roots are the heart of the plant, and plant vitality is inextricably linked in a hard lock-up with root vitality. In order to get the best from your plants, you absolutely must have happy roots.

If you start with a water-retentive medium, you cannot improve it's aeration or drainage characteristics by adding larger particulates. Sand, perlite, Turface, calcined DE ...... none of them will work. To visualize why sand and perlite can't change drainage/aeration, think of how well a pot full of BBs would drain (perlite), then think of how poorly a pot full of pudding would drain (bagged soil). Even mixing the pudding and perlite/BBs together 1:1 in a third pot yields a mix that retains the drainage characteristics and PWT height of the pudding. It's only after the perlite become the largest fraction of the mix (60-75%) that drainage & PWT height begins to improve. At that point, you're growing in perlite amended with a little potting soil.


You cannot add coarse material to fine material and improve drainage or the ht of the PWT. Use the same example as above & replace the pudding with play sand or peat moss or a peat-based potting soil - same results. The benefit in adding perlite to heavy soils doesn't come from the fact that they drain better. The fine peat or pudding particles simply 'fill in' around the perlite, so drainage & the ht of the PWT remains the same. All perlite does in heavy soils is occupy space that would otherwise be full of water. Perlite simply reduces the amount of water a soil is capable of holding because it is not internally porous. IOW - all it does is take up space. That can be a considerable benefit, but it makes more sense to approach the problem from an angle that also allows us to increase the aeration AND durability of the soil

 

[jaykush]

i prefer 0% perlite. works great

 

[Scrappy4]

i prefer 0% perlite. works great

Where do you buy it?

No really, do you use something else?
Scrappy

 

[OjoRojo420]

After reading Mandala's reasons and experimenting myself I tend to agree.

From Mandala's website:

Should I mix a soil amendment into the potting mix?

A beneficial soil amendment is worm manure or homemade compost. Do not use compost from autumn leaves (they contain almost no nutrients and no nitrogen). Mix 10-15% worm manure/compost thoroughly into the potting soil.

Do you recommend any particular product that enhances soil cultivation?

Endomycorrhiza is an excellent supplement. It is added very sparsely (approx.1% only) to the soil mix and greatly enhances overall health in the root zone.

Rock dust is another beneficial product. It contains up to 100 minerals! Adding Rock Dust mineral content to a soil increases bacterial activity and promotes new root growth. These extended root systems allow plants to increase their mineral intake, and provide for even stronger, healthier plants. It is used sparsely and is very inexpensive.

Is it necessary to add anything for drainage such as perlite, vermiculite, sand, expanded clay pebbles?

It is best not to add any additional materials to your potting soil. Horticultural grade potting soil is perfectly mixed for the best air-water ratio. Adding more non-nutritive substances depletes the water retention capacity of the soil, it unnecessarily "stretches" the soil and reduces the total amount of nutrients available to the plant, and it creates dry pockets in the container.

Adding a large amount of perlite/vermiculite (some growers add as much as 25%!) is a completely outdated practice from 30-40 years ago when there was only a very small selection of horticultural potting soil available for non-commercial gardeners. It is one of the unfortunate harmful practices in cannabis cultivation that many still cling to although they do not understand the reason or consequences.

Especially harmful is to fill the bottom of the container with coarse materials such as expanded clay pebbles. This is where most roots grow down looking for water and nutrients! If they reach a dry and sterile layer of substrate the delicate root hairs shrivel, valuable space is lost where the plant requires rich soil that stores moisture and minerals.

If you are planting outdoor and your soil is too compact a modest addition of perlite/vermiculite or sand helps to increase drainage. Humus, such as from compost, is the best additive because it also provides many microorganisms and nutrients to the soil mix.

KEEP IT SIMPLE STONER !

Ojo