AusBonsai

Hi guys,

I now see Enfield carries UXP.

From WhT I can gather it is very similar to pumice, but it seems to have a slightly more suitable particle size range.

Does anyone here use it, and hve compared it to pumice?

Anyone got pictures of it side by side close up? And by any chance at all done an air filled porosity and water holding capacity test?

G

I bought some from Tony - bougylover... haven't opened it yet.

What's the air filled porosity and water holding capacity test?

I bought one bag that I have played around with. Not very impressed to be honest. The water holding capacity seems pretty good, but its structural integrity is a bit questionable. There is a whole lot of very fine dust in the bag, and it seems to break down to dust easily (compared to pumice that is). A particle can usually be crushed between your fingers, albeit with some force. I dont think it would break down before akadama. I wont be putting it in a bonsai pot considering pumice is roughly the same price. Has been a good potting mix (but expensive) soil amendment for a few of my drier trees developing in nursery pots.... Not a substitute for pumice in my opinion. I always end up finding a use for the pumice fines, UXP fines are a very fine dust that doesn't feel like it would be good anything. Except maybe silicosis or it might keep slugs etc off things because it is very sharp. Take my opinion with a grain of salt though, my bonsai journey is still infantile.

W

UXP - "man-made pumice" ...bought a few bags from Enfield couple of years ago and have tested it against natural pumice. So far, I found similar root growth from pine and maples. I found there are more dusts in UXP bags than natural pumice so you may need to sieve UXP before mixing with other substrates to minimise cloggage.

I have used 10 bags of it. I've run out now but I would use it again no problem. I use it for both bonsai mixes and cacti mixes. I have no complaints at all. You do need to sieve out the dust ( or least I do) but it has not broken down or degraded after 2 years in the pot that I have noticed. pH is slightly alkaline but nothing that can't be adjusted if need be.
So far, thumbs up on this one..

Don't know if the same, but I use perlite to make my potting mix. It's very light and holds a lot of water. I found that very fine root hairs actually grow into it, I've weeded my bonsai pots and found that the fine roots penetrate the perlite so that it comes out with the weed. My mix is about 40%-50% perlite with coarse sharp washed sand and ordinary potting mix making up the remainder. Never had any trouble with it apart from any lying on top of the soil getting blown away in strong wind.

I bought a 20l bag of the 2-5mm, seems good to me - I went to sift out the dust and there was pretty much none. Nice uniform particle size. Cobb & Co at Pooraka stock it for those in SA.

I use this UXP along with zeolite and Martins native mix. This is my third year and I've had really good results using it. I run all of my UXP through a sieve as the dust can really build up. I've never had any issues with it breaking down and i imagine thats because i've removed the really fine particles.

Good luck with it

I wont be putting it in a bonsai pot considering pumice is roughly the same price.

Where are you located gyrza ? I can't buy pumice for anywhere near the price of UXP - and pumice is not even available at the moment. I sell UXP for $20 for 14l and Natural Pumice $30 for 14l. The 1-7mm pumice would have way more dust that UXP if it wasn't wet in the bag. The particle size of the pumice is atrocious - over half of it has to be seived away. I have been using scoria/UXP in a 50/50 mix for 3 years with no issue.

The breaking down myth is exactly that. I have a bottle with water in it and I placed some UXP in it on the 23/10/18. It is still the same as when it went in and cannot be crushed with my fingers.

I was speking to Rod Donegan from Ausperl about UXP not long ago and told him i was not happy with it in my mix when tried it for a few years.
He advised that it shodu be used in a mix with some organics as well.

I have real NZ pumice back in stock now, so happy to keep on using what I have good sucess with

Ken

Ken, what was it about the UXP that you weren’t happy about?

Matt.

Hey Ken,

This is the Auspearl Pumice right? 1-7mm or do you use a different size?

What’s the fines like? Do you find a good proportion of usable substrate in the 1-7mm bag?

This is the Auspearl Pumice right? 1-7mm or do you use a different size?

What’s the fines like? Do you find a good proportion of usable substrate in the 1-7mm bag?

I've been using the Auspearl 1-7mm for the last few months, and the particle size has been more consistent and there's been less fines than the natural pumice I'd been using previously.

Matt.