FlytrapCare Carnivorous Plant Forums

Sweet man. I may do that later this week because I'm expecting some seeds from Matt's free giveaway!

Coir sometime have those mineral deposits.....ill

UPDATE and Caution

After several months of observing the plants I placed into coir-based medium, I see strong signs of salt burn. I have transplanted all my plants back into a sphagnum peat based mixture for now. However, I like the physical properties of coir and I am still doing experiments on it, trying to soak and rinse it enough times to get the salts (dissolved solids or TDS) down to below 50 ppm (parts per million), a safe level for Venus Flytraps.

For the time being, I would caution anyone considering coir as a substitute for sphagnum peat that without further treatment to remove them, coir may contain too much soluble salts and minerals, despite manufacturer's claims that the coir is low in TDS, has been rinsed, has been subjected to rainwater leaching and rinsing through 1 or more monsoon cycles, etc.

I'm disappointed that coir may not be able to be used right out of the bag or bale, but still very interested in seeing if coir can be made usable because it has some very good air and water retentive characteristics and makes a growing mix with a great consistency when mixed with sand and/or perlite. In addition, coir would last perhaps 10 times as long as sphagnum peat moss because coir is so much slower to break down and decompose. While sphagnum peat moss can become dense and lose its air retention for the most part, coir may remain spongy and springy.

However, raw coir that one has not treated to remove excess soluble material is probably a bad choice to add to a growing medium.

Steve

Steve_D wrote:UPDATEAfter several months of observing the plants I placed into coir-based medium, I see strong signs of salt burn. I have transplanted all my plants back into a sphagnum peat based mixture.

Just a suggestion - try boiling it. You may have already done that, but if not, it seems like that might be the quickest way to diffuse the minerals into the rinse water.

What if you mix it with peat, like a combination of coir/peat/sand/perlite? That should lower the relative TDS, but would it lower it enough?

Nickrober wrote:What if you mix it with peat, like a combination of coir/peat/sand/perlite? That should lower the relative TDS, but would it lower it enough?

What's the point of using coir if you have to essentially water it way down in order to use it? The point is for it to be an alternative to peat.

nesler wrote:What's the point of using coir if you have to essentially water it way down in order to use it? The point is for it to be an alternative to peat.

The consistency and properties of coir are favorable to peat in some ways, namely it doesn't break down as fast and it's more "airy" which means there's less of a chance of root rot.

The only problem with coir is that it has a high concentration of minerals. In order to get those out, you have to soak it repeatedly in distilled water. Steve_D is doing an experiment with it right now to see how many times and for how long he needs to soak it before it's ready to use.

nesler wrote:Just a suggestion - try boiling it. You may have already done that, but if not, it seems like that might be the quickest way to diffuse the minerals into the rinse water.

That's a great idea. I'll try that approach on the next batch of coir, after I'm finished with my current soaking, rinsing and TDS checking cycles.

As Matt mentioned, I'm trying to measure the TDS of raw soaked coir and determine how long to soak the coir for maximum TDS concentration in the distilled or rain water, and how many times to soak and rinse it to bring the level down to below 50 parts per million TDS (total dissolved solids).

Boiling the coir in distilled or rain water may accelerate the process as you mentioned. Thanks!

Steve_D wrote:That's a great idea. I'll try that approach on the next batch of coir, after I'm finished with my current soaking, rinsing and TDS checking cycles.

As Matt mentioned, I'm trying to measure the TDS of raw soaked coir and determine how long to soak the coir for maximum TDS concentration in the distilled or rain water, and how many times to soak and rinse it to bring the level down to below 50 parts per million TDS (total dissolved solids).

Boiling the coir in distilled or rain water may accelerate the process as you mentioned. Thanks!

You're welcome. Let me know if it works.

But dosnt your coir get to compact when it get wet ? with no perlite or such..

Steve_D wrote:Yes, what Matt said. Pure coir holds an amazing amount of water, and just like pure sphagnum peat moss, it can become too soggy and dense and promote rot without some filler added to loosen and aerate the mix.

So just like with sphagnum peat based mixes, silica sand and/or perlite or other ingredients must be added to make a good, balanced mix that hold water, air, and retains the water for a reasonable amount of time (but not too long) if it is not sitting in a tray of water.

However, for germinating seeds, it's possible to use pure coir and just water it as necessary then leave it alone to dry some, which takes quite a while because of its high water retention rate.

I hope that explains it.

Steve

can we see an update?

Yes-- COIR update--

I bought a TDS meter and did some systematic treatment of coir. At first, the hydrated coir had TDS (total dissolved solids) of over 250, and some over 300. This is of course way too high a concentration.

So I tried soaking batches of coir. I found that a soak of 12 hours was as effective as a 24 hour soak in removing as much TDS per soak as possible, so I have been able to soak and drain the coir 2 times a day, and continue to do this for 3-4 days, maybe 5-8 soaks. Each soak lowers the TDS by about half, except when the TDS gets below 50 ppm (parts per million), in which case removal of the remaining TDS is less effective per soak. But that's OK, because under 50 ppm, coir is similar to sphagnum peat moss in TDS, and in fact in two tests the soaked, desalinated coir was lower in TDS than sphagnum after a 24 hour soak.

Now I'm trying some plants in a coir medium, with varying amounts of silica sand and/or perlite added to the coir. I have some Sarracenia, Drosera and Dionaea in coir medium right now, but I won't know until this coming growing season how well they like or adapt to the coir. At least, since I began to soak and desalinate the coir before use, it's not killing the plant, and that's a major step!

Although the salt burn experienced by the first plants I put in coir was disappointing, I'm very hopeful that treated coir might be able to make a good planting medium and an alternative to sphagnum peat.
Steve

Have you tried to soak them with hot water? It should bring a better effects, more solids could be dissolved in the same ammount fo water

great! next summer post pics of the plants you have in the coir, I'd love to see hwo they grew. sorry about your first plants. I bought a coir brick for my tarantula, and I was surprized how light and fluffy it was! I think even pure coir would make a great medium for a VFT or sarrcenia, if the salt was low enough. good luck!