Substantial K in rainforest through fall.

[Stone]

Let's not be personally insulting here.

Yes let's not. Perhaps you could point me to where someone was. Maybe your ''OK enough of this BS'' comment?, Anyone else maybe? You are demonstrating unfair bias Ray.
I thought that posting the throughfall data was worth doing but because it does not mesh with someone else's idea and because some people (me inculuded) aren't the type to easily back down, this kind of toing and froing is inevitable.
I don't see the big issue with it really. No one has threatened to send in the attack helicopters yet :rollhappy:

 

[Stone]

,

I as with most growers, would be happy if you guys could just point me in the direction of the miracle solution when you find it.

:rollhappy: I don't think that's going to happen Gary beause there ain't one.
For what its worth though (and that may not be much) I think a fertilizer with equal parts NH4-N and NO3-N is a good start for orchids. Maybe a K/N ratio more like 0.4 or 0.6 for profusly flowering orchids like catt dends and phals and multi flowering paphs. Maybe a K/N of 0.3 is enough for some paphs. I still believe a K/N of 0.008 is too low. I think a P/N of 0.008 is appropriate. Magnesium at half or less than the level of Calcium is important. I often blend 2 or 3 ferts as I am unhappy with all their formulations!
Sulphur should not be forgotten. Xavier mentions Manganese and boron higher than iron is the way to go judging from his wild tissue samples.
And what about silica? It is just as abundant as Ca in the habitat but hardly anyone mentions it. I think I read somewhere that there is a sinergistic relationship between Si, B and Ca! Thats what I'm using anyway.
And don't forget the seaweed and amino acids :rollhappy:
Oh and I forgot to mention the all important concentrations! When I'm happy with my fert mix, I give all the above vigorous plants an EC of about 0.3 to which would make N roughly 50ppm. I don't worry too much about it. Plants on cork get double that every second watering on average. The delicate Paphs like the parvis etc get about 25 or 30ppm N. I'm still learning how to feed paphs.

 

[Trithor]

Thanks Mike, up until a year ago I was a very casual feeder, never paid much attention to what I was feeding them, or how often for that matter. My plants all seemed to grow OK, with the only problem being when my fertigator malfunctioned and for about 3 months I was feeding at about 8x the recommended strength for tomatoes (that was a near disaster, and most of my plants still carry the scars from that maltreatment a year later)
After joining ST I became a lot more critical of what they get as fertilizer, and I read all of these k-lite/MSU debates with keen interest. Not knowing enough about plant nutrition, I don't lean to either philosophy as of yet, and as mentioned elsewhere am still busy feeding my main greenhouse with both types in the hope of seeing a marked difference. Unfortunately (or fortunately, I suppose that depends on your outlook) up till now there is no discernable difference between the two sides. I am acutely aware however that there are major differences to be achieved by improving my culture first. Although I have been growing for a few decades, there is still a lot I need to learn. Some things I am aware of, but am slow to implement the changes that would improve the culture. I firmly believe that in our climate (and probably every climate around the world) that GH volume is more important that GH size, ie a high roof is beneficial, and the higher the better. The greater the volume, the more the environment is stabilized and culturural inaccuracies are smoothed over. I know that I need to improve temperature control and air circulation, and I probably need to get rid of my Gouldians (the little buggers go through flower bud destructive phases). One of the best changes that I have made is to reduce the feed concentrations and apply more often on a more regular basis, ..... Now for the miracle formulation, that I will leave up to the experts to work out (one thing I do believe is that plants and animals have developed/evolved to grow at their best in the wild in the niche that they occupy (not talking about artificial greenhouse culture), or else they would not be growing there in the first place, but somewhere else. Anyone that has collected will tell you that they occure in very narrow/specific localities on the whole, with the exceptions being those species that we call 'easy', which occure in bigger colonies with a broader niche. I believe this debate will continue until we are able to identify what is in each species environmental niche and available to those plants directly and from the association with lichens, mosses and fungi. In the interim, I suppose we can tweak our plants feeding in order to attempt to optimize their growth, but I fear that where the tweak might be right for one, does not mean it will be right for the rest.

 

[Rick]

One of the best changes that I have made is to reduce the feed concentrations and apply more often on a more regular basis, .....I believe this debate will continue until we are able to identify what is in each species environmental niche and available to those plants directly and from the association with lichens, mosses and fungi.

Or NOT in the environment. Interesting human behavior that we first assume that something is missing that must be added.


I hope you all will take the time to check out those sufficiency standards for crop plants (the link to Clemson U agri sciences ) and compare with the scant in situ data available (from say Zotz or Naik).

By crop standards insitu orchids should be dead for lack of NPK (unless orchids are closer to blueberry than bell pepper). As you note Gary they are thriving in the wild, and that insite should be used as a guide for what they need (or at least what they don't need).


Also from looking at those sufficiency standards, all these same arguments about K usage and K toxicity could be had between the blueberry and Christmas tree growers versus the cantaloupe growers!!