Detoxifying over-fertilized plants

[ALToronto]

I don't want to hijack the K-lite thread, and I think this topic deserves its own space.

In the last couple of pages of the K-lite thread, a poster referenced a research paper that described a study in which absurdly high amounts of fertilizers were fed to some phals. The study concluded that optimum amount of K was about 1.5 times the amount of N and double the amount of P, all at very high doses. This is completely contrary to the results found with K-lite.

However, I have no doubt that large commercial greenhouses feed their plants all that and more to get them to blooming as quickly as possible. I'm not above buying these plants when they go on the discount rack (for experimenting with new mounts and living wall designs), and now well-meaning friends and relatives have started giving me these plants as gifts.

So my question is: what's the best way to detox them? The first thing I do is get them out of blue-stained sphagnum (yes, they're fed that much) into lava rock or a more typical bark/perlite/charcoal/sphagnum mix. I rinse off the roots and soak the medium in RO water, but I'm not sure if I should be doing anything else. I water only with RO for a couple of weeks, but I have no idea if that's enough to detox them, or too much. And how would I know?

 

[Rick]

This one may not be easy. I think (from some experience) that there is a good chance to see some kind of osmotic shock if you do this too fast.

I think its good to get them into rock of less water retentive bark (maybe Orchiata) if you want to keep to a potted format. I've had lots of success mounting phalaes. Including hybrids ( I mentioned I've never kept a potted phalae alive in my pre low K days, but did good with mounting).

Rather than going to straight RO, go to a soft water with hardness around 20-40 and alkalinity 10 to 15ppm. An orchid on a high K diet will have very low amounts of Ca and Mg, and needs these in frequent small amounts to get back to a normal balance.

Also Mg translates through plant tissues very effectively (Ca is much more slowly acquired). This is just my opinion, but when I added frequent small doses of Epsom salts, plants in this condition came around fairly fast. Epsom salt may be the closest thing to a "purgative" in this application.

Supposedly Mg can get into the plant via foliar feeding, but Ca pretty much has to go through the roots.

And maybe use a little kelp extract.

 

[Linus_Cello]

My guess is that there won't be an issue with "de-tox". First, these are hybrids that probably aren't as sensitive as species. Second, my guess that anything you do will be better than the conditions you bought these plants from a "big box store," super-market or hardware-type store (over-watered by employees; exposed to chilling air temperatures near the building entrance, wrapped in plastic and no air circulation, etc).

 

[Stone]

So my question is: what's the best way to detox them?

With the greatest of respect, I think we really need to get away from this notion that plants which are well fed are in a state of toxicity. This is simply not the case. Where is no proof that these plants (like the healthy ones in the study) are anything other than in a state of good health and will not stay that way? Where does this idea come from? Most of the best examples of orchid species around the world are fed this way! (apart from such high P levels) No need for detoxing!! A plant (any plant) will show signs of toxicity in poor root growth or crappy looking leaves. These plants do not show this so why assume they have some sort of hidden problem? If you want to ''harden'' them, just reduce the N. If you belive they are over-fed just cut everything in half or half again or half again but expect to see a reduced growth rate.

 

[Stone]

QUOTE] An orchid on a high K diet will have very low amounts of Ca and Mg, and needs these in frequent small amounts to get back to a normal balance.

Why does it need to get to these levels? These plants are obviously NOT deficient in Ca or Mg. or you would soon see it. What are the signs of Ca or Mg shortage if the root tips and the leaves are healthy.
What will happen if you don't do this? It seems to me that plants (including orchids) can function perfectly well with a widely varying range of nutrients as long as there is no gross imbalance. The phals in the study just do not show this to me. If there were a gross imbalance, they simply would not grow well.....surely?

 

[Ray]

I don't know if it holds true with plants, but it certainly does in people, and that is the concept of "feedback loops". If the level of one nutrient is elevated - even if it's in a non-absorbable form - it "tricks" the body into thinking it doesn't need to absorb more, resulting in deficiencies.

One of the best examples is the use of "Nexium" for stomach issues. It is a chemical containing a lot of magnesium, yet prolonged use of the product leads to a magnesium deficiency.

I view fertilizers similarly - if you apply more of something than a plant needs over a long period of time, it may very well throw off the internal chemistry of the plants.

If you look at the chemical analyses of throughfall and trunk flow from around the world, it averages out to be roughly a normalized 15-1-1-5Ca-3Mg (doing that from memory, so I might be off a bit), applied at somewhere between 5 and 25 ppm TDS whenever it rains. Seems to me that the K-Lite formula comes reasonably close to that, so I think it's probably the best we have, to this point.

 

[DavidCampen]

If you look at the chemical analyses of throughfall and trunk flow from around the world, it averages out to be roughly a normalized 15-1-1-5Ca-3Mg (doing that from memory, so I might be off a bit)

Do you have a reference for this?

 

[Ozpaph]

One of the best examples is the use of "Nexium" for stomach issues. It is a chemical containing a lot of magnesium, yet prolonged use of the product leads to a magnesium deficiency.

Ray, I've never heard of this before. Please supply some evidence. I note its 'listed' as a rare side-effect. I suspect, if its true, that its related to suppression of gastric acid affecting 'absorbability' rather than a drug effect. So I'm not sure its a good analogy. Interesting, though.

 

[DavidCampen]

An orchid on a high K diet will have very low amounts of Ca and Mg

Do you have a reference for this?

 

[Ray]

David,

A lot was from Benzing's Vascular Epiphytes, and some of his references.

Oz,

I was discussing that with my MD brother-in-law, and he's the one that mentioned it. I can claim no first hand knowledge.


Ray Barkalow
Sent using Tapatalk

 

[limuhead]

If you are trying to detox your orchids don't send them to Rehab, they might encounter some of those Hollywood types and go off the deep end...

 

[DavidCampen]

David,

A lot was from Benzing's Vascular Epiphytes, and some of his references.

Can you quote some specific text that said that?

 

[DavidCampen]

I don't know if it holds true with plants, but it certainly does in people, and that is the concept of "feedback loops". If the level of one nutrient is elevated - even if it's in a non-absorbable form - it "tricks" the body into thinking it doesn't need to absorb more, resulting in deficiencies.

One of the best examples is the use of "Nexium" for stomach issues. It is a chemical containing a lot of magnesium, yet prolonged use of the product leads to a magnesium deficiency.

Nexium contains only a tiny amount of magnesium; it is about 5% magnesium so a 40 mg tablet contains only 2 mg of magnesium. The active ingredient is the other 38 mg. Nexium can cause magnesium deficiency but this is because of its effect in decreasing stomach acidity due to its action as a proton pump inhibitor. The magnesium in Nexium has nothing to do with Nexium causing magnesium deficiency.

 

[Ozpaph]

Oz,

I was discussing that with my MD brother-in-law, and he's the one that mentioned it. I can claim no first hand knowledge.


Ray Barkalow
Sent using Tapatalk

Thanks.

 

[Ozpaph]

Nexium contains only a tiny amount of magnesium; it is about 5% magnesium so a 40 mg tablet contains only 2 mg of magnesium. The active ingredient is the other 38 mg. Nexium can cause magnesium deficiency but this is because of its effect in decreasing stomach acidity due to its action as a proton pump inhibitor. The magnesium in Nexium has nothing to do with Nexium causing magnesium deficiency.

That's what I was thinking but what's the mechanism? Iron needs acid to convert it from one ionic state to another to be absorbed. Is it a chelation effect?

 

[DavidCampen]

That's what I was thinking but what's the mechanism? Iron needs acid to convert it from one ionic state to another to be absorbed. Is it a chelation effect?

I was wrong about the hypomagnesemia being caused by reduced stomach acidity. Actually magnesium is absorbed in the small bowel and the mechanism by which PPIs cause hypomagnesemia is unknown.
http://www.google.com/#sclient=psy-...on.2,or.&fp=ced323dcb6c44588&biw=1280&bih=793

 

[Rick]

If you look at the chemical analyses of throughfall and trunk flow from around the world, it averages out to be roughly a normalized 15-1-1-5Ca-3Mg (doing that from memory, so I might be off a bit),

Note normalized ratio (not percent).

1 percent = 10g/1000gr (liter) = 10,000ppm. In throughfall/trunk flow your rarely find any of the NPKCa Mg more than 10ppm. More likely at less than 5ppm.

 

[fibre]

IMO detoxifying is the wrong term. I would feed those plants quite a lot at the beginning and slowly reduce the ferilizer over the next few month. I would try to adapt them slowly to my conditions.

 

[Ozpaph]

that sounds sensible

 

[paphioboy]

Interesting topic. Not referring to slippers, but for almost all other common orchid genera grown in the tropics (Vanda alliance, Cattleya, Dendrobium mainly hardcane hybrids, Phals, Oncidium alliance) you would be surprised at how much fertiliser is used here in commercial orchid nurseries. And with no observable side effects, apart from a little burn on leaf tips (only occurs rarely). Almost always fertilizer is applied as solids, in addition to foliar spray. I think plants adapt more readily than we give them credit for, so there is no real issue of 'toxicity' at high levels if the nutrients are in balance.