Pumice quality?

[wireme]

I've been in contact with a pumice mine on the west coast regarding bulk orders. I'm about 1000km from them so trucking is the main expense, this means the larger the order the cheaper the price per m3. If I do go ahead and order a large quantity I need to know the product is good. I remember reading in a thread here somewhere a mention of some pumice having high levels of something that's not so good for growing but I forget what it was. Being a large mine I'm sure they have chemical analysis available, I will ask for that + a small sample bag. Is anyone aware of specific characteristics to avoid or look for?

Thanks
Mp

 

[yenling83]

I've been in contact with a pumice mine on the west coast regarding bulk orders. I'm about 1000km from them so trucking is the main expense, this means the larger the order the cheaper the price per m3. If I do go ahead and order a large quantity I need to know the product is good. I remember reading in a thread here somewhere a mention of some pumice having high levels of something that's not so good for growing but I forget what it was. Being a large mine I'm sure they have chemical analysis available, I will ask for that + a small sample bag. Is anyone aware of specific characteristics to avoid or look for?

Thanks
Mp

I don't know of anything in pumice that's not good for growing if it's pure pumice. The sample idea is a very good one. One thing about pumice, is that the amount of dust and unusable fines that you get from one batch to another can vary alot. If there was just a place that sold it rinsed and the fines sifted already for a decent price that would be the way to go. That may exist, but I don't know where. I know of one place that rinses and will send you a bag of one size, however it costs more than Akadama in the US and you have to buy a min of 4 pallets.

A few things I think about with pumice-how one source of pumice compares with another? Pumice mined from one location is not created equally with another. I don't know exactly what structure is desired for optimal root growth. What type of weight, # of holes or other Structural composition is best and does this matter enough to make any differnce? I guess it would be difficult to prove.

 

[wireme]

Thanks Yenling, I could swear I have read a comment about some pumice from some sources being high in a certain mineral or element or something that's detrimental to plant growth but I can't find it now. Maybe was from another forum. I'll wait a bit and hope someone else chimes in.

 

[jason eider]

Second what Yenling said about batches varying. Recently picked up a sizable load, prob, 1/2 was unusable being very fine/dust.

 

[quietobserver]

Evidently the volcanoes never got the quality control memo prior to production. Seriously though count me in on the consistent inconsistency.I just buy small amts, so I don't exactly get the pick of the litter so to speak but often its outstanding but occassionally mediocre. Regardless, pumice could probably grow tap root on a gypsy...

 

[bonsai barry]

Have you tried looking for "Dry Stall" at your local farm supply store? Forty pounds for about $15-20. I sift it and loose about 1/4 or so (which I use in the kitty litter box).

 

[sikadelic]

Have you tried looking for "Dry Stall" at your local farm supply store? Forty pounds for about $15-20. I sift it and loose about 1/4 or so (which I use in the kitty litter box).

I Second the dry stall. This is my first year using it and I had little waste compared to turface. My only complaint is that you only have 1 size choice of 1/8". That's not really a problem per se, but if you want larger particles you will want to look elsewhere.

 

[wireme]

I could look for dry stall and check it out but it sounds like the particle size is smaller than my preference. I've been using 1/8"-5/8". The stuff I'm currently investigating is marketed as screened to size, hopefully effectively.

 

[GrimLore]

I could look for dry stall and check it out but it sounds like the particle size is smaller than my preference. I've been using 1/8"-5/8". The stuff I'm currently investigating is marketed as screened to size, hopefully effectively.

I find that Dry Stall along with around a third of Turkey Grit(larger type) works well for us. The grit is crushed granite and a bit larger adding some weight to the planting as well. I strongly recommend you wear something like this when sifting/rinsing any substrate http://www.globalindustrial.com/p/s...mpaignId=T9F&gclid=CPSPztCt57wCFTHNOgodOD4A5g

Grimmy

 

[ghues]

Hi Mp,
That source you speak about = Pemberton perhaps? I got a sample < 9mm they called it a horticultural mix - I liked it but they wanted bulk buys
Then I found a local garden centre that carried it (15lb bags) in 2012 so our club ordered a pallet load for re-potting. It works great
Michael Hagedorn has a good article on Pumice on his site http://crataegus.com/
Good luck

 

[wireme]

Yep Pemberton area, there's a couple mines in the area, the only ones in Canada I believe. Can you tell me the name of the garden center? Maybe I'll look into a pallet from them for comparison. The bulk order I've been negotiating is a massive amount but I may be able to share it with someone here doing a green roof project. Also if I have a lot extra I think I could re-use it yearly as winter protection mulch I think it would be a perfect material for that use.

The last few years I have transitioned from primarily granite based mix to granite/scoria to small amounts of granite/scoria with mostly pumice. I use small amounts of local organics in the mix too, bark, red-rot chunks, decomposed needle litter layer and charcoal. I like to find old burnt decayed logs in the forest with nice chunky and burnt debris. Some pics of this material in this thread. http://bonsainut.com/forums/showthread.php?11143-RMJ-challenging-re-potting