Orchiata

[goldenrose]

I spend most of my time trying to uncomplicated things, ....
I need to simplify my growing as much as possible. I never realized that bark was such a complicated variable, I must say it makes me feel somewhat silly and poorly informed!

This thread is not what I expected, I'm a K.I.S.S. person, I'm stickin' to what works for me & if it's not, then I'm aware of other possibilities.

Whew, this bark thing is very complicated. I just buy a bag of bark chips, make a basic mix, pot my plants and hope for the best! Perhaps that is why I don't grow very well?

I doubt it, orchids can be pretty adaptable!

 

[orcoholic]

It seems that everyone adding lots of amendments to the Orchiata are not having many problems with it regardless of whether they use ammoniacal or nitrate nitrogen.

Ray mentioned he's been using Orchiata for several years, but i'm pretty sure he grows most things in SH. The material from Lehua may not be in Orchiata, or may have a lot of amendments.

Quintal uses Orchiata, but adds a lot of sponge rock. I repotted a group of Den. lowii I got from them into my orchiata mix, and they just kept shriveling and died. I thought it was just some bad plants, but now i'm rethinking it. The plants came in looking fine, like most of their orchids. The same thing happened to an Epi with a clonal name of Flame Thrower (Can't remember the full name).

Is anyone actually using Orchiata with a fertilizer where the N is mostly Ammoniacal and has been using it for a couple years? It would be good to hear from someone with actual experience. My fertilizer has all Nitrate and I add Calcium Nitrate. I am also in my first year of using Orchiata.

 

[Roth]

It seems that everyone adding lots of amendments to the Orchiata are not having many problems with it regardless of whether they use ammoniacal or nitrate nitrogen.

Ray mentioned he's been using Orchiata for several years, but i'm pretty sure he grows most things in SH. The material from Lehua may not be in Orchiata, or may have a lot of amendments.

Quintal uses Orchiata, but adds a lot of sponge rock. I repotted a group of Den. lowii I got from them into my orchiata mix, and they just kept shriveling and died. I thought it was just some bad plants, but now i'm rethinking it. The plants came in looking fine, like most of their orchids. The same thing happened to an Epi with a clonal name of Flame Thrower (Can't remember the full name).

Is anyone actually using Orchiata with a fertilizer where the N is mostly Ammoniacal and has been using it for a couple years? It would be good to hear from someone with actual experience. My fertilizer has all Nitrate and I add Calcium Nitrate. I am also in my first year of using Orchiata.

Lehua is using only Orchiata so far...

For Orchiata with ammoniacal fertilizer, I do indeed use it, and so are all the Japanese. Most of the Orchiata customers growing phalaenopsis, and most of the hawaiians are using as well an ammoniacal fertilizer...

For Dendrobium lowii, it is typically one species that does not respond well to calcium nitrate at any time. I grow them too, but calcium nitrate make them drop their leaves pretty quickly for me... I use a high ammonium ratio fertilizer, and they show no problem. They do not like to dry too, and as a bonus, they must be repotted at the right time, when new roots appear at the base of the new growth. Not before, and for sure not when the new growth just emerges... That's the main cause of death for lowii ( and spectatissumum as well as sculptum, which have similar requirements...).

 

[Stone]

I am delighted to see that Xavier is back, Lets hope its not only for this job-related occasion. Here's my two cents worth regarding the pH issue in particular the urea-misconception as I call it. Ok, here it comes:
"everyone" knows that if you use urea the pH drops. But is it really so? Having a chemistry background, working wit it for 30 years, I simply cannot make that consistent with the basic chemical reactions that the urea undergoes through the transformation to ammonium and eventually to nitrate, if it does? What I experience if I let a diluted, say 100ppm, urea solution stand for a couple of days, is that the pH increases. This can be attributed to the enzymatic decomposition of urea into ammonia, which of course reacts with water to ammoniumhydroxide which is basic.
The ammonium part of the ammoniumhydroxide may in turn be transformed to nitrate, but is it not more likely that the plant absorbs the ammonium? After all if it has nitrate it has to reduce it to ammonium in order to use it? So, my question is therefore; where is the acid that has to be neutralised?
Using ammonium salts like ammonium sulphate is another story. The ammonium ion reacts acid with water and here we have acid, but this is not urea.
Comments?

Bjorn, I certainly have no chemistry background and far be it for me to know exactly what goes on but according to my reference ( and lets face it, thats all we have unless we have a lab and can do the experiments ourselves ) the Urea added to the media will transform to ammonium carbonate within 2 days
The reaction for ammonium is given as NH4+ + 202 (to) NO3- + H2O + 2H+ (You can explain that to me later:rollhappy
So Loss of nitrate added as nitrate does not alter the pH BUT loss of nitrate produced from ammonium will do so. So it is claimed that acidification is due more to this effect than the direct effect of ammonium. In short loss of nitrate from ammonium by leaching every time we water = acidification.
It is also claimed that this acidification can be prevented by use of fertilizers where the nitrate to ammonium ratio is 2 or 3 to 1. But I prefer to use higher urea/ammonuim than nitrate and add lime.
But lately I've been turing my attention more and more towards organic N forms and hopefully doing away with nitrate and ammonium additions? After all its more what the paphs have evolved with and its so difficult to get the balance just right with concentrated fertilisers. Maybe a combination??? As you know the late Jim Rentoul used only blood and bone twice a year and a calcium hydroxide drench twice per year and that's it!! (but he also put oak leaves in his mix which may have the best balance of nutrients?)

 

[DavidCampen]

DiAmmonium Phosphate (DAP) is a readily available fertilizer material; it has a pH of about 8 and the pH could be adjusted further with phosphoric acid based pH Down to produce a good buffer with a pH in the range of 6 - 8. A solution of this might be usefull as a soak for modifying the pH of bark.

 

[Bjorn]

Bjorn, I certainly have no chemistry background and far be it for me to know exactly what goes on but according to my reference ( and lets face it, thats all we have unless we have a lab and can do the experiments ourselves ) the Urea added to the media will transform to ammonium carbonate within 2 days
The reaction for ammonium is given as NH4+ + 202 (to) NO3- + H2O + 2H+ (You can explain that to me later:rollhappy
So Loss of nitrate added as nitrate does not alter the pH BUT loss of nitrate produced from ammonium will do so. So it is claimed that acidification is due more to this effect than the direct effect of ammonium. In short loss of nitrate from ammonium by leaching every time we water = acidification.
It is also claimed that this acidification can be prevented by use of fertilizers where the nitrate to ammonium ratio is 2 or 3 to 1. But I prefer to use higher urea/ammonuim than nitrate and add lime.
But lately I've been turing my attention more and more towards organic N forms and hopefully doing away with nitrate and ammonium additions? After all its more what the paphs have evolved with and its so difficult to get the balance just right with concentrated fertilisers. Maybe a combination??? As you know the late Jim Rentoul used only blood and bone twice a year and a calcium hydroxide drench twice per year and that's it!! (but he also put oak leaves in his mix which may have the best balance of nutrients?)

Thanks Mike,
This does explain it at least to some extent. Forgot about the carbonate part of the urea I do agree that nitrate run-off may produce some acidification by this mechanism, but I am uncertain whether the conditions that apply to soil would apply in our mixes? Whether the ammoniumcabonate from the urea produces an acid reaction or not seems to be the decisive point here. I do not know, but has a gut-feeling that it may give some alkaline reaction. At least that is what I measure on a dilute mix if let standing for a few days.
Another thing that may look silly is to put so much emphasis on this matter as long as we heavily flush our mixes, the explanation for the excellent results obtained with ammonium in the fertilizer is probably because the easy access for the plant. Because of the regular flushing, I do have my doubts about the conversion to nitrate as well.
I do adjust the pH of the water I use, so in my case, this may be the main pH influencing factor. Btw. I strongly suggest that everyone should adjust their pH, as else soft and suitable tap water often is adjusted to a pH of approximately 8 with sodium hydroxide or similar to prevent corrosion.
I have attached a dosmatic proportioner to my watering line so I have to use soluble fertilisers. Else, the ideas of Jim Rentoul still stands for me as prominent examples on how things can be done. I have all his books I believe, they are getting difficult to find these days.
Bjorn

 

[weiweidc]

Has anyone tried Kiwi bark? How does it compare to Orchiata?

 

[Ross]

Has anyone tried Kiwi bark? How does it compare to Orchiata?

I have used both with good results, so far. However, I prefer the Kiwi bark for two reasons: It is harder and less moisture retentive, which I prefer because of my high humidity in the greenhouse, and more importantly, the fine Kiwi Bark is a little smaller than the Orchiata Classic, and holds small Paph seedlings in place better. This allows the roots to establish themselves and grow more quickly.

That being said, if I were in a dryer growing space such as the house, I would probably use the Orchiata more and amend it with a small amount of CHC (for moisture retention) so I wouldn't have to spend as much time watering.

Good thread, BTW! Even though I'm reasonably happy with the growth of my plants, there is always room for improvement.

 

[Ray]

Ray mentioned he's been using Orchiata for several years, but i'm pretty sure he grows most things in SH. The material from Lehua may not be in Orchiata, or may have a lot of amendments.

About half my plants are grown in S/H culture using LECA; about another 25% are in straight Orchiata.

The plants I get from Lehua are in Orchiata plus about 10% spongerock, but I don't see that having much effect on the media chemistry.

 

[Rick]

Thanks Mike,
This does explain it at least to some extent. Forgot about the carbonate part of the urea I do agree that nitrate run-off may produce some acidification by this mechanism, but I am uncertain whether the conditions that apply to soil would apply in our mixes? Whether the ammoniumcabonate from the urea produces an acid reaction or not seems to be the decisive point here. I do not know, but has a gut-feeling that it may give some alkaline reaction. At least that is what I measure on a dilute mix if let standing for a few days.

The acidification is due to nitrifying bacteria (under oxic conditions) converting ammonia to nitrate. There are lots of water retentive pores in the bark matrix (which is why we use bark/moss/chc in the first place), that are chalked full of bacteria/fungi doing all kinds of stuff from nitrifying/denitrifying/plane old respiration from carbon degradation.

Non biological chemistry is minimal in the pot matrix. There's really not anything going on that isn't already known and quantified in a waste water treatment plant.

 

[Ruth]

I have most of my orchids in Orchiata. All of them seem to be doing fine, except for one Masd. coccinea, which I had repotted about a month ago into Orchiata. I think that I used the bottom of the bag of Orchiata and there must have been some concentration of the lime in the bottom of the bag. Part of the leaves would turn gray and dry up. I repotted it in sphag and it is doing fine now. The other thing I see is that when you repot with the dry Orchiata mix, it is hard get it to moisten up, especially the top layer of the potting mix. That said, I will continue to use Orchiata.

 

[Paul]

I just started to repot my plants in Orchiata. Looks like a very good bark. Easy to pot with, easy to wet just after repoting. I use 3 grades, depending on the plant size and species. for Paphs, only the Classic and Power.
I will tell about the results in a few months!! This is the good time to repot paphs, many new roots are starting now!

The maybe good thing is that my fertilizer is ammonitrate based... with low K and P and low to average alcaline water.

 

[limuhead]

Has anyone tried Kiwi bark? How does it compare to Orchiata?

I use it and it works fine. Not sure if it lasts as long because it is not composted. Composting any bark is pretty easy. I compost my large chunky bark by soaking it for a day, then coating it with Dolomite and then let it sit for a few weeks or until the dolomite has completely dried. I then rinse it and use it. So far I have had excellent results as far as roots attaching themselves to the bark.

 

[orcoholic]

Lehua is using only Orchiata so far...

For Orchiata with ammoniacal fertilizer, I do indeed use it, and so are all the Japanese. Most of the Orchiata customers growing phalaenopsis, and most of the hawaiians are using as well an ammoniacal fertilizer...

What fertilizer are they using?

Also, I grow a lot of phals in NZSM. Will an ammoniacal based formula harm them?

Roth - thanks for the type on the lowii's.

 

[Stone]

Xavier! While you are reading this, A question.
In an old post you mentioned doing leaf analysis of some emersonii and mastersianum etc. and you reported High nitrate and low Mo in the chlorotic plants and also low Fe and higher Mn, B and Zn in the wild plants.
My question is did you do a sutstrate analysis? (habitat soil). How did it compare with the leaf analysis of the wild plants?
Only answer if you want to

 

[Stone]

I just started to repot my plants in Orchiata. Looks like a very good bark. Easy to pot with, easy to wet just after repoting. I use 3 grades, depending on the plant size and species. for Paphs, only the Classic and Power.
I will tell about the results in a few months!! This is the good time to repot paphs, many new roots are starting now!

The maybe good thing is that my fertilizer is ammonitrate based... with low K and P and low to average alcaline water.

I repotted some plants in it this week too. I agree I think its going to be good!
But instead of mixing smaller and large grades I have been making a mix with 4bark, 1 charcoal, 1 chopped moss, 1/2 chopped oak leaves and some sand. I know people say to use it straight but I really like the way this mix behaves in the pot! Lots of air but still good moisture. I think I finally found ''my mix''I will also report results later.

 

[Ozpaph]

I thought oak leaves were quite acidic?

 

[Stone]

I thought oak leaves were quite acidic?

Yes but no more than sphag or peat. Are you using straight bark for everything?

 

[Ozpaph]

Yes but no more than sphag or peat. Are you using straight bark for everything?

no. paphs - 50% orchiata, equal coarse perlite/charcoal/CHC
Catts - 60% bark, 30% charcoal, 20% CHC

 

[Rick]

Yes but no more than sphag or peat. Are you using straight bark for everything?

Have you had a chance to read that article that Naoki linked? Sphag is only initially acidic. If you don't add fertilizer the acidity washes out after a few months of watering. The strong and chronic drop in pH in sphag is due to the bacterial buildup from adding plant roots and regular feeding.

The effect in bark is less, I assume the effect in lime/dolomite impregnated Orchiata is even less.