I just saw someone else post a similar demise on another forum which makes me believe the gigantea is far more sensitive than other phals.
Now I honestly don't want to threadbomb this thread, it seems to have exploded in activity recently but to me the original fertilization requirements are the problem people are facing.
I don't know how some people manage to fertilize so heavily on some of their mini's. I won't speculate on that but I feed my mini's 25ppm N maximum.
I know for a fact that Vanda's, Dendrobiums and even Cymbidiums can do fine with 25 ppm N per watering, Phalaenopsis anyway. They do benefit from a bit more once they are bigger but 25ppm is enough to sustain any orchid for at least a year at which point possibly heavy feeders will show signs that they want a little more.
A little more being up to 50 ppm max.
The care guide says at the beginning to feed up to 125 ppm N and recommends doubling that in hot weather.
ES, I won't speculate what happened with yours but I know you like to fertilize the heaviest out of everyone I know on here going up to 1000ppm in total for your Vanda's so if you were following the recommended dosages, my money would be on that concentration doing damage.
Also the statement of I did this but it can't have been that because the orchid did not die for another 2 months means very little as it routinely takes orchids 2 months to die. They don't just drop dead overnight. Any changes take a couple of months to mark the ultimate demise although I agree that dryness is probably less of a factor than feeding wrong if you compare the culture to nature grown plants.
I know there are millions of discussions on fertilizers and at the end of discussing it for days we all just go back to doing what we always do - feed vanda's at 1000ppm or whatever else we have been doing.
Just to put it in perspective every single flower I have shown this year has been grown with 25 ppm N max.
I know I'm still a bit of a novice with only 40 orchids flowered so far. Some people have been growing for 40 years and would disagree with me.
The point I am trying to make is that maybe, just maybe a Gigantea is more sensitive than other phals.
So if you have flowered 1000 phals, you might then end up failing every time with a Gigantea.
That's my 2 cents on the matter. Why use 5 times as much as another grower who succeeds with 5 times less fertilizer. That is a big difference to me. I know most phals can tolerate such a wide variance as orchids consume so little anyway but with the more sensitive ones it might make a bigger difference.
I honestly want to know why the Gigantea's that don't make it with people at home ultimately don't make it. Other phals have no problem growing indoors and my comments aren't just plucked out of thin air.
They are just a theoretical observation and I don't want to cause upset, I want to play detective, to me dryness can't be too bad, cold temps don't seem to affect it too much, air flow and light can be provided. Maybe I am off on this, I know some people think it makes no difference to the health of a phal and maybe with most phals it really doesn't as they can tolerate either but a Gigantea seems to be a bit different to other phals.
What do you think? Has anyone here been feeding over 100ppm N - and just to clarify if one feeds 100pm N that means one has to be feeding an overall concentration of roughly 500ppm in total fertilizer.
If so, has the plant been able to handle it ok?
Conversely has anyone tried feeding it 25ppm N, so 125ppm total fertilizer concentration? What has been the result? Healthy growth or signs of deficiencies?
When I think of the name Gigantea, I think that it would need a giant amount of fertilizer to make it big and strong. But that ultimately might be causing problems?
Last edited by Shadeflower; 09-13-2021 at 01:00 PM..
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