Sphagnum ?

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Rick,
Do you think that a MSU fertilizer would buffer enough to compensate for the acidic nature of the sphagnum moss? It seems to have ample calcium and magnesium.
 
Rick,
Do you think that a MSU fertilizer would buffer enough to compensate for the acidic nature of the sphagnum moss? It seems to have ample calcium and magnesium.

MSU don't seem to have much in the way of carbonates or bicarbonates, which is what buffers aqueous solutions.

I used to just about solely use straight RO water for both fertilizer makeup and between fertilizer misting and irrigation water. For the past several months now, I've been using my well water thinned down to 5-10% (its very hard'n crusty) with RO water and getting very good growth out of mounted and moss/basket combinations of phals and bulbos. At this rate I have a hardness down in the 25-50ppm range with similar alkalinity, and sphagnum potted plants seem to be growing much better than before.

Most of the other really good growers in our society, like Ed M use the Nashville tap water for both regular irrigation and fertilizer make up. The hardness of Nashville tap is 90-100 ppm, alkalinity of about 60 ppm and conductivity of 180.

So I wouldn't rely on MSU fert alone for pH buffer without adding some source of bicarbonate to offset acid substrates.
 
In real soil/bog conditions the bacteria will often alter pH and alkalinity conditions.

Typically under aerobic conditions many bacteria in the process of metabolizing will acidify conditions, while under anaerobic conditions many bacteria actually release alkalinity and cause the pH to go up. It's hard to predict in pot conditions what the bacterial community will end up as and how they may effect pot conditions, but ultimately they will be the driving factor as substrates age.
 
oK,
So to buffer the media, what are the favorite materials?


Oyster shell and lime are pretty standard. Bone meal is also supporting, and adds more phosphate. These are all solids that can be used as a top dress.


What is the quality of your tap water? You can usually get a report from your municipality if you are on city water.
 
I had my water tested in a lab and sent the results to the Blackmore co. Dr. Bill Argo emailed back and he suggested the MSU 15-4-17 South Florida Special formula based on my lab results.
The Magnesium was low.
He said alternatively I could use the MSU Well Water formula but that I would need to add Epsom salts every 2 to 4 weeks.
So I feel pretty confident that the water/fertilizer matches up well.
I've been using chicken grit mixed in with some of my paphs and phrags and some bulbos. I'm not sure about how much they are buffering, the crushed shell is so hard...

What form of lime do you use?
Where do you get it?
I was also thinking of using the crushed limestone they use for aquariums, the
pellets are pretty uniform in size.

Thanks again,
Jim
 
I had my water tested in a lab and sent the results to the Blackmore co. Dr. Bill Argo emailed back and he suggested the MSU 15-4-17 South Florida Special formula based on my lab results.
The Magnesium was low.
He said alternatively I could use the MSU Well Water formula but that I would need to add Epsom salts every 2 to 4 weeks.
So I feel pretty confident that the water/fertilizer matches up well.
I've been using chicken grit mixed in with some of my paphs and phrags and some bulbos. I'm not sure about how much they are buffering, the crushed shell is so hard...

What form of lime do you use?
Where do you get it?
I was also thinking of using the crushed limestone they use for aquariums, the
pellets are pretty uniform in size.

Thanks again,
Jim

If you are in Florida your water is pretty hard and buffered already (especially if your analysts are suggesting the use of the well water formula). So aside from the occasional recommended use of MgSO4 I don't think you really need to add any more lime based top dresses to your mixes.
 
I do foliar feeding, so pH is less of an issue.

Also, as an update, I'm starting to get great root growth on several species...
 
UPDATE on sphagnum:

I just checked some Paph callosum, niveum, acmodontum, and delenatii, and all are going gangbusters with new roots.
 
I think it always depends on your growing conditions. Any medium is fine depending on your local conditions. Sphag could work but no way would it work for me. I only use it for Pleuro's.
 
I've been leary in the past, results were not good with sphag, then came the suggestion - it should be loosely packed in the pot. It's made quite the difference, I think. I started with phals & psychopsis, have put a couple of phrags in it & most of my laelias are in it, so far so good!
 
Sphagnum moss is great for orchids and it will promote root growth. If you are having trouble with moss being too compact...why not add styrofoam peanuts to the mix to prevent compaction as the moss ages. My paph mix consist of coconut husk and sphagnum moss with spongerock or pumice stone added and they grow really well!

Paphman910
 
Hi guys,
Been awhile since anyone updated this thread.
How are your plants doing in sphagnum?
Thoughts, comments, recommendations?
Thanks,
JT
 
Hi guys,
Been awhile since anyone updated this thread.
How are your plants doing in sphagnum?
Thoughts, comments, recommendations?
Thanks,
JT

Well I know you've been following the sphag basket system thread I started this winter.

There were a few things I potted (or had potted) in moss, but in standard clay, plastic or aircone pots. Side by side with the baskets, they did not do as well. A few in aircones got a lot of additional holes drilled into the pots, and now I'm seeing new growth.

So far I think its still pretty important for the system to breath a lot, and I think the sand is helping to keep the moss from breaking down too fast.
 
Hi Rick,
I've got a ton of seedlings in 3-1 bark to perlite.
They are doing OK, but I really expected better growth.
I am thinking about trying the seedlings in sphagnum to see if
I get better growth.
Not sure if I should use straight sphagnum or mix in other
inorganics.
Your thoughts?
Thanks!
 
I've gone from sphagnum to mixes of bark/sphag to straight bark (or chc mixes) and now going to primarily sphagnum again ( or more likely sphagnum with some sand). I like to use those plastic berry containers with lots of slots in them.

I used to have a lot of seedlings do great for the first year, and then stop (and often trickle away plant by plant). The lower K higher Mg has stopped the stall (especially for big multi species) regardless if they are in a primarily bark or sphagnum mix. But I tend to get better roots faster with mixes that have at least 1/2 of the volume in chopped sphagnum.
 

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