Against the "Status Quo"

[Fairorchids]

I actually beg to differ. Salts will migrate across a membrane (= cell wall) from high to low concentration, but it is not an instant migration.

Thus:
Application of fertilizer will still be effective after a heavy watering.
Heavy watering is needed after 3-4 days of no watering.
Done in reverse, you waste a lot of fertilizer, either by watering 2-3 times with fertilizer mix, or by washing away the fertilizer the plants have not taken up yet. We then wash out excess in the next watering (drenching).

I sort of have the proof in my Paphs. Whenever I have had a Paph for 6 months or more, I can see a marked difference in the leaf shape & width, between leaves it had coming in (pointed & narrow), and those it grows under our conditions (blunt & wide).

Likewise, I purchased some 6-8 Phrags from Oct to Feb. All were single growth plants, or plants that had grown only single growths for several years running. All are busting 2-4 vigorous new growths under our conditions.

[stonedragonfarms]

Originally Posted by Fairorchids

I actually beg to differ. Salts will migrate across a membrane (= cell wall) from high to low concentration, but it is not an instant migration.

Thus:
Application of fertilizer will still be effective after a heavy watering.
Heavy watering is needed after 3-4 days of no watering.
Done in reverse, you waste a lot of fertilizer, either by watering 2-3 times with fertilizer mix, or by washing away the fertilizer the plants have not taken up yet. We then wash out excess in the next watering (drenching).

I sort of have the proof in my Paphs. Whenever I have had a Paph for 6 months or more, I can see a marked difference in the leaf shape & width, between leaves it had coming in (pointed & narrow), and those it grows under our conditions (blunt & wide).

Likewise, I purchased some 6-8 Phrags from Oct to Feb. All were single growth plants, or plants that had grown only single growths for several years running. All are busting 2-4 vigorous new growths under our conditions.

A few points:
a. I believe that you would need to set up a control to verify your results...I'm assuming that you mean that subsequent growths under your cultural regime result in more substantial growth. That being said, there are a number of factors that come in to play here besides fertilization regimen/technique; light, humidity, differentials between day and night temperatures, water quality, media & frequency of watering just to name a few.
b. Unless I'm mistaken, there is a difference in root structure and the ability to take up nutrients between those orchids that are epiphytes and those that are terrestrial/semi-terrestrial; I believe that the premise of this thread was to deal with those orchids that are epiphytes/lithophytes in "nature"; it has been shown that in these epiphytes, ion exchange occurs in the first few moments of the roots velamen being exposed to nutrient solution.
c. I'd be curious to see the growth rates/forms of these same plants if all of your cultural practices were observed, without the application of any fertilizer.
Just my $.02
Adam

[DeaC]

Ladies and Gentlemen...I've now seen the light and what you all say makes sense. I don't grow vandas or anything like them but if it's good enuf for Dr. Motes, it's good enuf for me. This is a great discussion and a real eye-opener!

[Fairorchids]

The concept makes sense for Vandas grown in empty baskets (with exposed roots). For plants grown with medium in baskets & pots (as I grow all my epiphytic orchids), it does not. I have to wet the medium first.

[james mickelso]

Nitrogen, which is produced by lightning in the atmosphere, is in the rain drops. Phosphorus/potassium is in the leaf litter/animal and bird poop/Decaying wood that makes up where the orchid is growing it's roots. When it is the rainy season, raining day and night, there is little potassium and phosphorus available to the orchid's roots. At the end of the rainy season the phosphorus/potassium becomes available to the orchid due to the fact that the rain isn't washing it away as soon as it becomes available. I'll also beg to differ with Dr. Motes. Mature velamen absorbs moisture almost instantly and becomes saturated and won't absorb any more moisture beyond a certain point. Fertilizing media seems a waste to me. The orchid doesn't grow roots quickly enough to absorb it so it is wasted. Difficult to just fertilize the roots I know except for mounted plants.

[NYCorchidman]

Even during the rainy season, plants get what they need. Rain pattern also differs, short burst of shower in the early afternoon is very common, although the rain might fall for hours or even days on end, but this is not the norm.

Even then, the animals continue to poop, and with each rainfall, it is washed over the plants.

Apparently, the poop has be washed over to the plants to be available, whether it is rainy or dry season. Orchids or other plants won't just jump on the dry poop and feast on it. lol

[Optimist]

I loved your post of coursr, but the generalization "all plants need" worrys me, not because I think you are wrong, but because these plants fill a specific nitch in the environment, living where no other plants live and so on. Not a one to one correlayion, of course, but you could not say yhal "all animals" need xyz list of nutrients. They need different amounts, they make their own and store it and excrete it differently. But of course, they need more nutrients than commonly found in the fertilizers. Often something is not bioavailable unless it is paired with another micronutrient.

[DavidCampen]

I would like to know about any plant that can make nitrogen, phosphorous, potassium, calcium, magnesium etc. Perhaps with a bit of selective breeding we can get it to make gold or platinum though I would be happy enough even with silver.