New Potting Technique, Root Health

[Ray]

I measure the pH once and mix up the same formulation every time, but that's easier with RO, as it's always going to be the same. A periodic check is a good idea, just to be comfortable.

Orchids3: That pH range predates Bill Argo. Even Rebecca Tyson Northen talks in the 6.0-6.2 range 30 years ago.

Also, those so-called "nutrient availability" charts are relatively meaningless for us. They all come from one study involving the pour-through of solutions and SOIL, so shows how readily the ions can be entrapped or released at specific pH levels for that soil formulation (and its "cation exchange capacity") and one particular fertilizer.

For the most part, orchid media components interact very little - if at all - with nutrient solutions (i.e., the cation exchange capacity is near zero), so the simple fact is that if the mineral exists as an ion in solution, it is available for the plant to take up. Granted, under some pH conditions, molecules may become so complex in size or shape that it blocks absorption, but fertilizer producers are pretty savvy about such stuff, so any mineral in them will be available at pretty much any pH to which we expose our plants.

[Douglas Scanlan]

Yes, as the individual who is conducting this experiment, I can say I agree with Royal and Anthony the most in their theories of why my roots have struggled even as the plant appeared healthy from the crown up, and the blooms lasted 5-6 months. Growing orchids in glass stones and wire baskets is much more adventurous and off the charts than I initially realized it would be. When I bought these plants, they had thriving green root masses in soaking wet (but brand new) Sphag (that is how the store kept them). Transferring them to my experiment was a polar opposite. However, after 6 months, I simply do not have any NEW root growth on this plant, and therefor I am not confident that this is ever going to work (although half the original roots did survive the 6 months). I will continue some variation of this potting technique, and I still don't like Sphag or bark or any of that- they are great for dry households but in my humid home it is problematic. Even though Sphag is great when it's new, it just breaks down and looses its antifungal properties too quickly, and requires re-potting too often for my liking. My goal was to create a potting technique that would come closest to a natural Phalaenopsis environment for the roots. Which means airflow, light, and the ability to water and dry out in short successive cycles. I realize many of you do not agree with the short drying cycle but I still say this is how Orchids function in nature. My apartment is very humid, and the roots really are supposed to react with air humidity every bit as much as with direct H2O in the pot. I just got sick of the whole concept of keeping roots all couped up in a dark dank pot in direct contact with damp material 24-7. And worrying about how much water is the right amount of water in such a pot- tedious guesswork. Still, new roots are not forming with the system I am experimenting with now, so I think Ray's S/H might be the best solution. I'll still use a wire basket if Ray thinks a basket will not screw up the wicking ability of the S/H potting media. Ray??

[billc]

Originally Posted by Douglas Scanlan

My goal was to create a potting technique that would come closest to a natural Phalaenopsis environment for the roots. Which means airflow, light, and the ability to water and dry out in short successive cycles.

Why not just mount them??

Bill

[Douglas Scanlan]

I'm going to try mounting someday as my next project. I don't know much about it, but I assume it helps to have outdoor humidity that is close to what I get here indoors with my hudifiers. Colorado is a pretty dry place. Also, I bet keeping mounted Phals watered is at least as high maintanace as what I've been doing with glass stones, maybe more? At least with S/H I can achieve a lower maintanace watering routine.

[Connie Star]

There is a medical pH tape that comes in a roll- it's used in body fluid testing. I just get some from the clinic where I work, but it's got to be available from medical supply houses. Or, find a doctor who will give you the roll when there's only a little bit left and no good medically.

[Douglas Scanlan]

Thanks Connie, I was thinking of a swimming pool tester? Or fishtank tester?

[Connie Star]

I think there are a lot of different ways to test- I get occasional almost empty rolls of pH tape in my office, so that is the cheapest for me. But the fish tank and swimming pool tester kits would do more. I bought a water testing kit at Home Despot but it was limited and pretty expensive. Still looking. Other ideas? Cost? Maybe I should just get RO and start from scratch

[Douglas Scanlan]

If you go the RO route, Ray's company (First Rays) sells an orchid fertilizer that is specifically designed to be be used with RO water, thereby automatically setting the correct PH with every application.
I'm not going to that extent. I have not even gotten around to testing my PH yet.
Here is the URL for Ray's site if you have not been there:
Welcome to First Rays LLC

[Leisurely]

Someone said in this thread that Phalaenopsis do not like to dry out. I have large plants that have aerial roots that hang down three feet under the bench. The plants get watered once per week and they are quite happy. I believe that your dead root are from too much water.

[Douglas Scanlan]

Thanks Leisurely.
I think you are right and wrong on this. I think you are right in that Phals roots don't need to be kept as consistently moist as most seem to think. Fequent air drying combined with frequent watering is what they are naturally suited for in their native habitats, which is why I was experimenting with the potting technique with glass stones and wire baskets. The roots want to absorb humidity from the air just as much as soak it up from direct contact.
However, I think you may be wrong that overwatering is the reason my roots were dying. My roots were not rotten and dark, to the contrary they were pale, dry and shrivelled. Being potted in glass stones in a wire basket would require frequent watering (just as in their natural habitat they would want frequent rain showers).
Your orchids that are happy with a once-a-week watering are not potted in glass or something non-organic are they? Most organic potting mediums for orchids stay moist for at least a week or more.