Perlite and beyond: the pros and cons of various drainage and aeration amendments

[Bullfrog44]

Jaykush - I wouldn't pay 5$ for commercial compost either. However high grade organic compost and EWC is a different story.

I was thinking of paying 300$ for a yard of vermi-compost from http://sonomavalleywormfarm.com/

 

[heady blunts]

i thought we were discussing a fully amended potting soil mix?

 

[sgapetti]

on a quest on finding a proper media for drainage/aeration, i came across sepiolite
http://en.wikipedia.org/wiki/Sepiolite , high porosity and light weight, any input on this ?
That said , thanks everybody for a very interesting 3D full of info

 

[skullznroses]

Good thread I am currently trying to find something to replace perlite in my mix. I have switched out about 50% of it with vermiculite but want something larger for the other 50%. I always like perlite but since I add my soil to my veggie garden I don't want the security risk when the perlite starts to float away.

thats why you dump it in the woods and grow ditch weed

 

[geo420]

I dont know if this has been added but I have a few here, Cocoa shucks/shells, WOULD BE KILLER FOR GROWING CHOCOLATE STRAINS, makes the soil smell great just like chocolate.

Also Im using pine bark and I really love Cypress mulch(I leave mine out 1 yr before using, its cold and kills ALL bugs from Florida.

Castings probibly the best organic additive out there, I didnt see it in the first ten posts. TEA TEA AND MORE TEAS FROM THESE LITTLE HELPERS.

sawdust, (try not to use from a chain saw, instead I go to a sawmill), great for replacing perlite.

 

[ixnay007]

on a quest on finding a proper media for drainage/aeration, i came across sepiolite
http://en.wikipedia.org/wiki/Sepiolite , high porosity and light weight, any input on this ?
That said , thanks everybody for a very interesting 3D full of info

Yeah, I was looking around for the product that VG recommended, I found that the sanicat line makes 2 or three possible substitutes, 1 is the pink (calcined danish molar clay, comes out pink) two is the non clumping sepiolite (with added oxygen, I'm guessing something that off gasses oxygen when wet..) and third is a clumping one, but it's bentonite (I'm guessing the calcium version) which is one of the ingredients in greensand (the other being sand). The fact that it clumps isn't great though, I'm guessing it may be a bit small, even if it's list as dust free..

Any input VG, madlib or others?

 

[heady blunts]

i can't find rice hulls or undyed pumice stone

i might have to resort to using some perlite.

at least i've got lots of calcined DE to help it out.

the question now is, do i break my back pounding out hardwood charcoal? probably worth it in the long run.

i already promised myself i'd screen out the fines in my DE this time around. ithere's only 60+ lbs of it!

 

[ixnay007]

on a quest on finding a proper media for drainage/aeration, i came across sepiolite
http://en.wikipedia.org/wiki/Sepiolite , high porosity and light weight, any input on this ?
That said , thanks everybody for a very interesting 3D full of info

I had a look at some of the characteristics, it's got a pretty high PH, but I guess a magnesium/silicate clay would have that sort of profile.. It's also fairly delicate, I don't think that's a positive.

Found a greek company that sells calcined attapulgite:

http://www.geohellas.com/products/industrial-absorbent-solutions/ABSO-PRO-Universal

 

[ixnay007]

More info on sepiolite:

http://ressources.ciheam.org/om/pdf/c31/CI020854.pdf

page 9 says:

In Spain, commercial-scale experiment was conducted in a polyethylene greenhouse to evaluate sand, perlite, rockwool slabs and sepiolite (a local fibrous structure, claystone material mainly based on hydrated magnesium silicate) alone or mixed with leona(r3d%ite by volume) and organic fertilizer with 60% content of humic substances.
Results shown that higher yields were obtained with perlite and sepiolite (4/20-mesh plus
leonardite) and rockwool (Martinez and Abad, 1992). The authors suggest sepiolite as a new substrate for horticulture, because it has good performance under conditions of saline water, no pollutant effect and has a low cost. The total pore space of sepiolite is 78,13% the Air Filled Porosity 43,87% and the easily available water about 2%. Perlite and sand were the materials that kept the lowest E.C. until the end of the experiment

Obviously, used in hydroponics, it holds a lot of air.

 

[delta9nxs]

calcined clays and de are two distinctly different substances, formed in nature by different processes, with nearly identical physical and chemical properties. so why not use the cheaper substance? whatever it is in your area. i get turface in 50 lb bags for 10 bucks near my home. turf supply companies. other calcined clay names are agsorb and others in the us and seramis in eu. i'm sure there are many other brands available.

they are all mined from different sites and so will have slightly different chemical profiles but, along with de, once calcined become largely inert.

i have tested turface for ablating and it was negligible at 3 months. giving off approx 40 ppm at .5 in ro water beginning at 5 ppm.

i have never used de but have extensive experience with turface. i used it alone for many years in hand watered nursery pots and in "hempy's".

for many years i recycled it and eventually accumulated over 2 tons of it. it can be washed and reused many times. those concerned with hardness will be happy to know that the breakdown rate is .03 % at 20 years. not too bad.

when i used it alone i screened it with regular aluminum window screen to eliminate fines. you will lose about 30% of the mass doing this.

now i am not screening because i use rice hulls as a cutter. my primary mix for the device we are working on is 3/1 turface/ricehulls.

this is an extremely "fast" mix designed for hydro. it produces an air porosity of approx 35%.

this is appropriate for a 64 oz pulse of nutrient solution every 90 minutes into 2.5 gals of medium.

if you are hand watering a better mix would be 4/1 or 5/1 depending on frequency.

i have cut turface with coco, perlite, pine bark, peat, and some other stuff that i can't remember now. if you cut it for porosity you do not need to screen it. just wash it all really well.

both the turface and rice hulls have a substance ph of about 6.2.

while i feel the turface and probably de do not give off much of their silicon maybe the mere presence of it acts as a contact prophylactic.

the rice hulls have the highest silicon content in the plant world at slightly less than 20%. this and the high lignin to cellulose ratio keeps them from breaking down rapidly. the decomposition you see at the end of a grow is almost all cellulose. i personally do not reuse them.

i get rice hulls at 18 bucks for a 50 lb bale/bag at a horse stable near me.

another big advantage to this mix is that it contains no salt.

silversurfer, hey buddy! the cat litter is dangerous because although it may be calcined clay it is not fired at a high enough temperature to form a permanent ceramic.

mad librettist, you have inspired me to mulch! nice thread!

i think the most important thing to remember building your own mix or using a pre made mix is to check air porosity, which is described as the percentage of void space in your medium.

roots grow best in a warm, nutrient rich fog, which is laden with o2.


http://forums.gardenweb.com/forums/load/cacti/msg1219545027416.html

https://www.icmag.com/ic/attachment.php?attachmentid=25916&d=1253811029

 

[mad librettist]

check out stall dri. it is a mix of turface abd calcined DE.


ythe two have diffrerent chemical properties. they complement each other well.

 

[cody2white]

I used these in a couple bags. I really like it and my buddy swears by them.

http://www.plantlightinghydroponics.com/growstones-grow-media-substrate-125cf-p-3546.html

 

[sgapetti]

More info on sepiolite:

http://ressources.ciheam.org/om/pdf/c31/CI020854.pdf

page 9 says:



Obviously, used in hydroponics, it holds a lot of air.

thx ixnay, i appreciate it. i am testing sepiolite as we speak outdoor and indoor as well. i will update the result here later on. Keep up the good work everybody.
Peace S

 

[oldguy]

i can't find rice hulls or undyed pumice stone

For rice hulls check out beer brewery places.
or grow organic.com.

Cheers

 

[heady blunts]

thanks old guy!

i try to keep it local if i can.

i ended up sourcing crushed lava rock. they even had multiple sizes! i went for 3/8"

 

[oldguy]

Anytime hb, Always nice to keep it local. Also some pet store may have it as bedding material. Cheers pal!

 

[sneaky_g]

Chunky perlite can "cook" with other amendments without any ill effect right?

 

[ClackamasCootz]

Perlite is inert, i.e. no problems other than to your finances

CC

 

[Azeotrope]

So, I find this thread very instructional and just down right interesting. I tried to read through the whole thing..... I can't remember how many times Zeolite has been mentioned, but I get a kitty litter that is nice and chunky Zeolite Clinoptilotite and use that. Lots and lots of good research out there showing zeolite as an excellent item to add. I get 25lbs for like $7.00. Not too pricey I think.

This time I added it to a very nice bedding mix I like called Miller's Mix along with Miller's compost and some additional coco. Then I ammended with some flower tone, blood meal, kelp meal, 'extreme gardening's Mykos and a local all-natural Tomato food that is similar in design to flower tone, but has some "edible mushroom extract" that they claim is their magic ingredient.LOL

Zeolite seems to be great for moisture regulation, airation, helping to make K more readily available and promoting more efficient nutrient availability/uptake/regulation from what I have read. All I know that when I have used it over the years (when not playing with coco drain to waste which I am now done with), I have had very healthy and happy grows.

 

[Azeotrope]

I tried to edit my last post (didn't go through) to point out that Zeolite Clinoptilotite is actually just the "High Silicone" variant of Zeolite Clinoptilolite. Have just figured that this is cheap, easy and discreet to source and who can argue with a little extra Si in their mix? Especially since it isn't allways the most plant available mineral.

At any rate, even though my base - Miller's Mix - has perilite, I add lots of Zeolite and that is especially nice for making it gritty, well draining and good at holding moisture after I add extra compost and coco.

Regards to all and Merry Christmas, Happy Holidays and well.... Just plain old Goodness to all!!!!!!