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Hydrogel crystals/water absorbing crystals

BigCarnivourKid

It's been one of dem days
Posting this because several of us were thinking about using them in our CP soil.  The problem with them is that when they break down, they may fertlize the soil.  According to the Gardener's Supply catalog I got today, Terra-Sorb is potassium-based and breaks down into fertilizer.  Other types of these water absorbing crystals are sodium-based and break down into salt compounds.  While some CPs are tolerant of fertilizer, like some Nepenthes, others like Venus Flytraps aren't. So be aware of this if/when you use them.
 
I saw these crystals in Lowes about a year ago. I got the company name and  I looked them up and I called them. I explained the situation, about cp's and they told me that there is nothing toxic in them. They said that every ingredient was completely inert. They even sent me a free sample.
With the claims that they make it seems to be perfect for cp's. I don't remember all the claims now, but I think it says that they can  hold like 3 times their volume of water, and slowly release the water so that you won't have to water as often. I think there was other claims too, but I don't remember. I went on the cp listserv and asked if anyone knew anything about it.
I got one reply that said don't use it it'll poison cp's. If I remember right she said about the same think that you're saying, except she said it was some nasty chemical. So I never even opened the bag. I decided that it wasn't worth the risk.
 
I think I'll give it a try with some d. spatulata.
I can't see the chemical breakdown occuring to quickly. I generally use sodium based crystals, so I'll try those.

joe
 
The crytals will break down in about a years time. They are a two part compound, one is the potassium or sodium based compound and the other is acrylamide. Obviously the potassium/sodium is toxic to CPs but few people know about the acrylamide. Acrylamide is a potent neurotoxin/carcinogen. In low doses it is generally tolerable by the body but the higher doses can get nasty. Because of the acrylamide the manufacturers of these products recommend they only be used for ornamental plants in situations where you are looking to have to water less often. Keeping them constantly wet will leach the acrylamide out faster and if you grow your plants on a tray system it will just be hanging around there. My advice would be to forget using it.

There is rumor of one company that makes a starch only based water gel but I have yet to find it.
 
The benefit is you don't have to water as often. They are like magic, I love them and used them for indoor plants when I was working in that industry. I've often thought they'd be helpfull, and I think I'll try to get some to try on some CPs. I believe the good quality brands are carbon based, but I'll have to look into it.
 
Doesn't spaghnum absorb three times its volume in water? Seems like a safer alternative perhaps.

Also on the topic of growing media, i just picked up a bag of rockwool that somebody was throwing out, vaguely recalling a discussion of its use in CP culture. Does anybody use rockwool for CPs? I tried mixing a bit in when i uppotted my ventricosa, but i wasn't sure what properties it contributes.
 
D muscipula,
You're right spaghnum does absorb alot of water and act similar to the crystals. You're also right about it being safer to use with cp's. But there is a problem with spaghnum. It grows in wetlands just like cp's, and it's habitat is being destroyed just like cp's. There are farms that produce and manage the growth and harvest of spaghnum, but there are also sources that take it from the wild and sell it for a profit. I have read alot of stories about people opening a bag of spaghnum and finding a whole pitcher plant.
You're right spaghnum is probably the best growing media that we'll ever have. But if we could find a safe alternitive, then we could reduce the damand for spaghnum. Which is the first thing I thought about when I read the claims of the crystals. Too bad we don't have a crystal that has a acidy ph and breaks down safely or better yet won't break down at all.
 
D

Rockwoll is often used to root cuttings (though I personally have found this method worthless.) I would guess you could mix it in to any mix requiring LFS as the properties are somewhat similar. That being said I would recommend you only try the mix on an expendable plant incase things go wrong
 
  • #10
Thanks Ozzy, i heard on the listserv once that even the managed farms tend to get pitcher plants in the spaghnum, but i agree it's still disturbing.  I personally try to err on the side of the sand /perlite in mixes, for the very reason you mention.

So, if rockwool has similar properties to lfs spaghnum, why is it not more commonly used?  It seems, considering the topic in question, that it would be a good alternative.  Just wondering.  I've not been using it long enough to get any feel for how well it works.  All i know is that it looks just like that fiberglass insulation that is supposed to be so dangerous for your skin and respiratory tract!
wow.gif
 
  • #11
One important thing to remember when using rock wool it is recommended that you first condition the rockwool before using it as a media. Conditioning consists of soaking the cubes for 24 hours in an acidic solution.
This removes any impurities and corrects the ph of the cubes.

Coir is the true media of "tomarrow".

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  • #12
Explain, my friend. What is this coir?
 
  • #13
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (Tim @ May 08 2003,11:30)</td></tr><tr><td id="QUOTE">Explain, my friend. What is this coir?[/QUOTE]<span id='postcolor'>
In Webster we trust:

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">coir

n : stiff coarse fiber from the outer husk of a coconut
[/QUOTE]<span id='postcolor'>

Thanks Khai, i didn't know that about pretreating rockwool.
Why is coir better than eg rock wool?  Just curious.
 
  • #14
One problem with coir, that I noticed a few weeks back, I can't find any. I looked at Lowes and every greenhouse I could think of and everybody looked at me like I was crazy when I asked for it. I gave all the names I could think of, cocopeat, coir, coconut husk. That didn't help either, I think it confirmed to them that I was crazy.
Only thing close I could find was the coconut lining for hanging baskets.
Let me know how the rock wool turns out.
 
  • #15
D

Rockwool is not used as an alternative because it is pretty expensive when compaired to LFS. It is also a lot more difficult to come by, I have never seen rockwool in a nursery while LFS is in every Lowes/Home Depot.
 
  • #16
Is rock wool rot proof? That alone would make it ideal in my book--set up the terrarium and forget it.

Steve
 
  • #17
It is resistant to rot being pretty much pure silica if I recall correctly. However, you couldn't just forget about it in a terrarium as the media will still build up toxins and need to be replaced.
 
  • #18
One way to aquire coir is to buy it at pet stores.
Its sold as a compressed brick marketed as a reptile/amphibian beding, this stuff may actually be prefereable as it seems to have been leached well.
Coir is supposed to be stable in the pot for 3 years, it has a fairly stable ph when compared with peat. Not to mention its completely renewable and does not tax a natural resource such as peat.
Heres a nice little article on rockwool.
http://www.genhydro.com/artfaqrw.html

Grodan makes a 1/4" cube that can be mixed with expanded clay and sponge rock, makes a nice airy moist media.

Rockwool does not rot because it is inert. It is composed of silicon oxide and various other rock material.
It does however eventually build up excess minerals which need to be flushed periodically.
Usually by the time this happens youll want to refresh with new media anyway.

Heres some info on Coir.
http://www.rbgkew.org.uk/ksheets/coir.html

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