Does anyone grow paph/phrag in rockwool with success??

[Tony]

I had a tendency to underwater before, both out of habit from growing epiphytes and also because bark and other organics turn into goop very quickly in our summer heat. Now that I've switched over to inorganics I water 3-5× weekly depending on weather. The rockwool holds enough moisture that I could probably get away with less, but it is airy enough that I'm not afraid to keep the plants wetter than I used to be able to and they seem to prefer it.

 

[southernbelle]

When I experimented with Grodan cubes years ago, it was available in hydrophilic and hydrophobic versions, so you were able to blend them in your preferred ratio. Apparently that's no longer the case.

Yes, you are right. Only one type seems to be available. And these appear to be hydrophilic as after a week they are just beginning to dry on top. This could be a problem.

 

[Tony]

Yes, you are right. Only one type seems to be available. And these appear to be hydrophilic as after a week they are just beginning to dry on top. This could be a problem.

Maybe a problem for things that want to dry out like Cattleya, but not for moisture lovers. I have Paphs, Phrags, Brassia, Phals, and Catasetum alliance plants all thriving in it, as well as some non-orchids like Hoya and epiphytic cacti.

 

[southernbelle]

Maybe a problem for things that want to dry out like Cattleya, but not for moisture lovers. I have Paphs, Phrags, Brassia, Phals, and Catasetum alliance plants all thriving in it, as well as some non-orchids like Hoya and epiphytic cacti.

What do you mix with it and what percentage?

 

[Tony]

What do you mix with it and what percentage?

Perlite or LECA depending on pot size, roughly 50/50.

 

[Ray]

All of my slippers are in S/H culture with LECA.

 

[Guldal]

From the recent thread on my vigorously growing P. druryi:

I grow [all] my paphs in a non-organic medium, Greenmix, mainly consisting of rockwool (diabas), perlite and lignite, i.e. both waterabsorbing and waterrepellent material.
When properly used, in a short while a nice layer of moss will form on top of the medium... the medium shouldn't be allowed to dry out completely, but the waterrepellent elements should allow for air and some dryness for the roots...
Our local mastergrower, mr. Hans Christiansen from Orchidégartneriet in Fredensborg, swears to it, some people at my local orchid society seems to hate it... Actually, it appears to me, that the question of growth media is the thing most likely to bring on something akin to religious war among orchid growers!
In this, parallel to so many other aspects of life, my own rather agnostic maxim would be: choose the growth media(s) you feel comfortable with and get to know it real well, learn from your errors, and don't change what works well! Or maybe it might be appropiate to quote St. Paul in this instance: "...test everything; hold fast what is good" (1. Thess. 5:21)
Kind regards, Jens

 

[Brabantia]

Interesting discution! Have you compared shreded synthetic foam like the one used in cushion with rockwood? What is exactly LECA and is this material available in Europa. If not is it existing an equivalent in Europa?

 

[Ray]

Interesting discution! Have you compared shreded synthetic foam like the one used in cushion with rockwood? What is exactly LECA and is this material available in Europa. If not is it existing an equivalent in Europa?

LECA is Lightweight Expanded Clay Aggregate, and it was developed in Europe for use as an aggregate in lightweight concrete, allowing concrete building to be constructed taller. It was later co-opted for hydroponic growing.

Atami's B'cuzz Hydro-Rokz is probably the best one out there, as it was reengineered specifically with hydroponics in mind.

 

[Linus_Cello]

LECA is Lightweight Expanded Clay Aggregate, and it was developed in Europe for use as an aggregate in lightweight concrete, allowing concrete building to be constructed taller. It was later co-opted for hydroponic growing.

Atami's B'cuzz Hydro-Rokz is probably the best one out there, as it was reengineered specifically with hydroponics in mind.

Is Atamai available in the US? It appears to be only Europe? https://www.atami.com/en_gb/hydro-rokz-8-16-mm

Do you get it from CA?
https://shop.sparetimesupply.com/products/b-cuzz-hydro-rokz--br-45-lt-5948.html

 

[Ray]

I don't get it at all, any longer. I just use Hydroton from my nearest shop.

Before ATAMI sold the Hydro-Rokz brand, they repackaged it for me under the "PrimeAgra" name. Back then I imported 40' containers of it periodically from Europe, but later they had an agent in Canada that maintained inventory, so I cut back to buying a few pallets at a time from them.

A few years later, Atami set up an agency in the Caribbean somewhere, so I did business with them, but they have not been particularly aggressive about marketing the stuff in the US, so it's really hard to find.

 

[spujr]

I don't get it at all, any longer. I just use Hydroton from my nearest shop.

Before ATAMI sold the Hydro-Rokz brand, they repackaged it for me under the "PrimeAgra" name. Back then I imported 40' containers of it periodically from Europe, but later they had an agent in Canada that maintained inventory, so I cut back to buying a few pallets at a time from them.

A few years later, Atami set up an agency in the Caribbean somewhere, so I did business with them, but they have not been particularly aggressive about marketing the stuff in the US, so it's really hard to find.

You know of a vendor in US where you can buy smaller quantities?

 

[Ray]

No.

 

[Teresa Koncolor]

I find a mix with at least 50% rockwool to be more forgiving if you forget to water. I probably use a 50/50 perlite /rockwool mix, although I have started to reintroduce some large bark chunks (about 10 percent) because I cant find large perlite chunks...small grade perlite clumping seems to cause concentration zones that affect water retention, ...the bark helps to break it up as the perlite moves around and settles with each watering

I got something called Growstone recently which feels and looks like big perlite pieces.

 

[NYEric]

Yes, but not in the bottom of pots, only on the top with perlite and moss.

 

[southernbelle]

I got something called Growstone recently which feels and looks like big perlite pieces.

I use both the GS-1 and GS-2 sizes of Growstone (which is an expanded glass product) instead of large perlite. I like it because it does not crush or breakdown. However, it has been discontinued and is no longer readily available. I hope they bring it back.

 

[Phred]

I haven’t grown anything in rock wool myself but spent the day with the late Azhar Mustafa of A&P Orchids in Swansea Massachusetts. He grew everything in a rock wool based medium. This product also contains what he called hydroponic styrene and perlite. He had 10’s of thousands of Paphs, Phrags, and Cymbidium thriving in the mix he manufactured and sold as Infini-Mix. His family is still running A&P Orchids and still sells his mix... attached are photo’s of the products.

 

[SouthPark]

Maybe a problem for things that want to dry out like Cattleya, but not for moisture lovers. I have Paphs, Phrags, Brassia, Phals, and Catasetum alliance plants all thriving in it, as well as some non-orchids like Hoya and epiphytic cacti.

The Cattleya orchids probably don't actually require roots drying out in terms of their water tolerating capabilities. The problem occurs if the water around the 'regular' roots is allowed to stagnate ----- lodged there for relatively long periods of time. The 'regular' roots require enough oxygen in the water to stay alive. Otherwise, parts of the roots die, and rot etc. So both growing media and method of watering and air-circulation can be important (apart from other things) for the orchid's health.

But then there are the 'non-regular' roots, which the orchid may produce (when they adapt) to handle being under-water permanently - the roots and base of plant that is - underwater. The roots either adapt (or die), or they actually grow other roots that aren't quite the same as regular roots. These are those roots seen growing in those glass containers filled with water. As long as the person is somehow able to keep things in that water under control (ie. prevent algae and unwanted things from growing and dying and putting a spanner in the works of the controlled 'system', and also provide a certain amount of fertiliser every once in a while - while keeping the water environment under control), then the Cattleya (and those other plants people grow with roots dunked in water) can just keep growing.

As to whether or not those non-regular roots can stay alive under-water indefinitely, I don't know whether these still require the 'still' (motionless) water to be adequately oxyenated - or not. Or whether the growers swap out old water for new water every once in a while.

I'm not a fan of keeping the orchid roots and stem etc dunked in water - with some leaves taking some weight of the plant along the pot rim. Too fiddly to control the system maybe. And that sort of setup (orchid dunked in glass container) looks somewhat ridiculous. Whatever works for those growers is fine I guess.

Also ----- interesting situation about 'moisture lovers'. At the moment, I'm not entirely sure that all paphs require their roots to stay moist. They probably can handle some drying...... or at least some of them, or ones that have adapted.

I have two paphs growing excellently in volcanic rock alone - for about a year or so now. No other media in there. At the moment, it just appears that these paphs don't get any issue with a dry state. I haven't gone for relatively long periods in dry-state though. These particular plants are beyond the juvenile stage though. I don't know what would happen if the same condition were to be applied to baby or relatively small seedling or cloneling orchids ----- maybe not a good idea for small plants that aren't big enough or well established. Not sure. But I can certainly go ahead later to see what happens ----- such as grow small plants in suitably small diameter volcanic rock media.

I also have an Oncidium Twinkle growing in 100% volcanic rock - for about a year too. That one has not only flowered, but also two new growths coming out of it, and the spike is getting its second wave of flowers developing at this time. The media and roots in this orchid's pot does get dry by the next day.

About usage of 'rock wool' .... opening post ..... if one has spare plants to try on, then might as well give it a try ---- for a few plants. But not try it on the rare/expensive ones of course. And as soon as something doesn't look right ----- then definitely intervene right away.

Question --- is there supposed to be some health concerns with rock wool?

 

[terryros]

Orchid roots need oxygen to stay alive and function. Oxygen is not transported to the roots from the leaves, so it must be available in the root zone. It is not water that kills orchid roots but lack of oxygen. The amount of air space in the potting media probably mostly determines the availability of oxygen to the roots, but pot design, water source, and method of watering probably play a role. I am five months in to a trial of growing everything (Phrags, Paphs, Catts, Miltonniopsis, Phals) in pure Growstone (smaller size for smaller pots). I am cautiously optimistic. I think large chunks of rock wool could leave enough air space in a pot, but would worry about rock wool completed compacted around roots.

 

[Teresa Koncolor]

I use both the GS-1 and GS-2 sizes of Growstone (which is an expanded glass product) instead of large perlite. I like it because it does not crush or breakdown. However, it has been discontinued and is no longer readily available. I hope they bring it back.

I ordered a bag online, the larger one. I didn't realise it had been discontinued. I got it with similar size Coco pieces that came in a huge bag. Half and half make a stable moisture, airy mix I've just started using but not on paphs, but lithophyte/terrestrial types like zygopetalum.