Paph philippinense 2016

[SlipperKing]

Bjorn, I grow my along the side of my roths. The key for me is plant size. For years I had the nagging problem of basal rot hitting any philie I had at the time. Then came along Rick L and his crazy idea of basket culture. "What the hell, it can't hurt. I'm not getting anywhere with philie in pots" Once I figured out what to put in the basket to keep enough moisture around the plants took off. I have had no rot issues for the past 2 + years with philies in baskets and they're always damp to wet. My most recent philie from Tom-DE in a pot was fine but got rot (as always)! Rather then unpot and place it into a basket, I top dressed it heavily with NZ sphagnum. Whala! Rot stopped in its tracks. NZ is the major component in my baskets as well. Apparently for me anyways philies prefer to grow in acidic environment. The other issue was the growth rate for me was so slow, but hold on! R.L. came through once again with all his talk of "micro" feed ratios. So, once I cut my NPK rates way, way down the plants sped up.

 

[Bjorn]

Thanks Rick, growing i one thing, but how to make them bloom, that seems to be my challenge. Rot is one important aspect, you are right, mine became much better once I reduced fertiliser levels and perhaps reduced K played a role as well?

 

[Justin]

They also like cattleya light levels.

 

[Happypaphy7]

Thanks Rick, growing i one thing, but how to make them bloom, that seems to be my challenge. Rot is one important aspect, you are right, mine became much better once I reduced fertiliser levels and perhaps reduced K played a role as well?

I know some people follow the low K thing here, but isn't K related with resistance to disease & environmental stress?

K is very important macro element in that regard as I always understood.

And it's funny because I was reading rather an old article by Dr. Wang regarding Phalaenopsis culture. Plants fed with well over 100 ppm of K did the best in both growth and flowering. Lower than 100, not as good, even lower, sever signs of deficiency (premature death of lower leaves and discoloring), no K, plants died in one year.

 

[Paphman910]

I know some people follow the low K thing here, but isn't K related with resistance to disease & environmental stress?

K is very important macro element in that regard as I always understood.

And it's funny because I was reading rather an old article by Dr. Wang regarding Phalaenopsis culture. Plants fed with well over 100 ppm of K did the best in both growth and flowering. Lower than 100, not as good, even lower, sever signs of deficiency (premature death of lower leaves and discoloring), no K, plants died in one year.

Heard that as well.

 

[gego]

I suppose using low K was not because the specific plant doesn't need a good amount of K. It could be either that plant is very efficient in taking K or the media used has a good amount of K available already. A good example is roth, the soil chemistry showed a very small amount of K yet the foliar analysis showed K as high as N.

Nutrient availability of organic media like bark needs to be considered. Lots of studies have shown that it has a good amount of K and P already. Providing more K will just cause Ca and Mg deficiencies.

 

[Bjorn]

Most orchids are naturally adapted to low fertiliser levels and will thus, at best, not benefit from excessive fertilisation. The problem with too high fertiliser levels is not the growth, but the tendency of attracting deceases etc. Lower fertiliser levels seem to be beneficial for the plants resistance to eg rot. Whether or not reduced amount of potassium is beneficial is a topic that are open, but most fertiliser ends up on the floor and is as such a waste anyhow.

 

[paphioboy]

I have had no rot issues for the past 2 + years with philies in baskets and they're always damp to wet. My most recent philie from Tom-DE in a pot was fine but got rot (as always)! Rather then unpot and place it into a basket, I top dressed it heavily with NZ sphagnum. Whala! Rot stopped in its tracks.

Interesting! I grow my philies the opposite way you do. I let my philies dry out between waterings and find they don't do well in moss or even top-dressed in miss as I feed them heavily. Perhaps the big difference is in water quality or frequency of feeding...

 

[gego]

How heavy do you feed? Maybe you can quantify it a bit.

Thanks

 

[paphioboy]

I apply a few pellets of sheep manure every few months. I avoid applying during the rainy season.

 

[gego]

That is heavy I suppose.

 

[Rick]

I know some people follow the low K thing here, but isn't K related with resistance to disease & environmental stress?

K is very important macro element in that regard as I always understood.

And it's funny because I was reading rather an old article by Dr. Wang regarding Phalaenopsis culture. Plants fed with well over 100 ppm of K did the best in both growth and flowering. Lower than 100, not as good, even lower, sever signs of deficiency (premature death of lower leaves and discoloring), no K, plants died in one year.

Actually K is inversely related to disease resistance. I found a lot of papers but some of the interesting easy ones were trials that looked at ability to withstand disease challenges depending on the ratio of K and Ca in the leaf tissues (Fluid Fertilizer Institute). I linked this paper to ST multiple times years ago when I brought up low K.

In short disease resistance (to erwinia in bean plants) was fantastically better when calcium concentration exceeded potassium concentration in the leaves.

There were some other papers I found on the biochemistry of resistance in plants (which involves the use of salicylic acid. When a plant is "challenged" by disease organisms (bacterial, viral, and fungal) it starts trying to dump K and intake Ca. If the plant has been fed a heavy K diet and tissues are maxed out, it will not be able to pull Ca up. K is antagonistic to Ca.

As per the Wang paper I've been growing lots of Phalaes (species mostly, but a few hybrids too) for five years now with K applications less than 5ppm (over 2 years at less than 1ppm) with great growth, blooming, and 0 mortality. The problem with Wang's work was that he didn't hold the form of N constant as he decreased K. He changed the ammonia / nitrate ratio, and ended up with toxic levels of ammonia at the low K doses. Ammonia is a super cation in its own right and is antagonistic with K, Ca, and Mg. Nitrate is an anion and doesn't antagonize cations. So a plant (actually this works the same for just about any living organism) overdosed with ammonia dies of K, Ca, and Mg deprivation. In most of the organisms I work with its usually the loss of Mg that gets them first, and in green plants (where Mg is the core molecule in chlorophyll, acute ammonia toxicity usually nails the chlorophyll early on.

 

[Rick]

http://www.fluidfertilizer.com/pastart/pdf/36p16-19.pdf

Here's that Fluid Fertilizer link.

The erwinia challenge only shows Ca tissue concentration but the botrytis challenge shows the Ca: K ratio (as inverse due to antagonism).

So in order to get the Ca tissue concentration high enough to fight erwinia the Ca will be considerably higher than K.

At least one paper I looked at on the stress alleviating aspects of K in plants starts with the premise that plants with K deficiency are susceptible to disease. However, most K in orchids is just luxury storage, and the point of deficiency is very low.

 

[paphioboy]

Actually K is inversely related to disease resistance.

That is true for foliar diseases on many crops but the relation between K and root diseases is less distinct.

 

[gego]

From this article I'm reading,it says "plants deficient in potassium will not produce enough proteins despite an abundance of available nitrogen.Instead, incomplete protein such as amino acids, amides and nitrate accumulate in the cell. Inadequate potassium levels leads to the decline of starch while soluble carbohydrates and nitrogen-based compounds accumulate. Leaves that have excessive amounts of soluble carbohydrates turn soft and fleshy and are often perfect candidates for pest and fungus attack."

I still have to see an article or a study that demotes K to a secondary nutrient. Different plant species will differ in their ability to uptake potassium to be specific or to all nutrients in general. The article says, "there is a highly controlled selectivity process involved in the uptake of nutrients by plants and that is the reason why the plant does not contain the same ratio of nutrients inside the plant as found in the soil."

 

[gego]

I think undesrtanding a plants' synergism and antagonism between mineral nutrients is very important and knowing their preference in what it exclude or absorb nutrients based on the concentration of nutrients provided to them. And one way to know this is to study their native habitat and environment. There is a very specific balanced system in where they grow. Knowing that specific balanced plant nutrition and apply that to the kind/type of media used, the stage of the plants' growth and the growing environment.

Ok, this getting too long. All I'm saying is that K is still a primary nutrient but the amount of this nutrient with respect to the other nutrients especially calcium and magnesium, that we supply will differ from plant to plant and the type of media used. For example, the use of bark which has K already on it. If your supplied nutrient has additional good amount of K with a minimal Mg, very likely mag deficiency will happen. And probably Ca too.

Just sharing.