# Water



## Stone (Feb 13, 2013)

I realize watering is probably furthest from the minds of the Northeners but ''watering season'' is not that far away.

Anyway, at our club meeting the other night it was mentioned by in passing that there is a growing trend amongst some paph growers here to sit their plants in water over the growing season and i'm also experimenting with this this year. It got me thinking: If so many of these plants do well with wet feet, then maybe the method of letting them dry between waterings is misguided? If they enjoy so much water without their roots rotting then its obvoiusly not the water causing the problem but possibly an imbalance in the bacterial population in the mix...insufficient numbers of supressive bacteria which feed on the pathogens as occurs in a natural ecosysyem.

I had a look through an old orchid book (1951) to find the following lines. "
'' So far as comopst is concerned, the Cypripediums (paphs) are adaptable to numerous materials. They can be potted exclusively in tan-bark (spent bark from tanneries), good Todea fibre (like osmunda), course leafmold and cow manure and various native barks stripped from dead trees and leafmold and humus gathered in the forest''

Many of these materials are now known to supress pathogens for up to 2 years where as pine bark for only 6 months or so!

With regard to watering, the 1951 advice was: December (June in the north) 
'' It is practically impossible to overwater the great majority of orchids this month, so give AT LEAST! two copious waterings EACH day, one in the morning and the other at nightfall, or at some time about sunset when the sun has lost the intensity of its heat''
''Wooden reseptacles require very close attention and plants mounted on fern fibre or other quickly drying material such as a block of wood need constant dipping''....''Make the plants grow by regularly watering them''

All this water and such a water retentive mix and no root rot!

When you think about it, during monsoonal downpours, the plants can be saturated for days at a time and thrive! on it. So theoretically and in the right environment ( warm and windy) you should be able to water every single day or more and get the ''wild vigour'' that we all want. maybe we are paying too much attention to feeding techniques and not enough to setting up an environment where we can ''really'' water the plants as they have evolved to thrive on.

Just a thought.
Mike


----------



## ehanes7612 (Feb 13, 2013)

might have something to do with the oxygen content in the water....standing water would have less oxygen content as bacteria growing and algae dying off ..moving water is going to have less growth in it so more oxygen and less bacteria therefore less rot..i make my mixes so i dont have to water so often ..watering twice a day or even once a day wouldnt be practical..but even in those kinds of mixes..really hot summer days require watering everyday


----------



## dodidoki (Feb 13, 2013)

There is a thread in ST about in situ pics of volonteanum. These plants are standing always in water. Rot is caused as you mentioned not by water I think but by building up of salts, bacteria and lack of oxigen. In nature roots are constantly washed around by fresh rainwater full of solved O2 furthermore much of rainwater washed out pathogenes mechanically.
I thought about daily waterings with fresh RO water, sometimes low TDS K-lite....


----------



## wjs2nd (Feb 13, 2013)

I've started, though out the entire year, watering more. I think I was letting things get a little to dry. I have noticed and believe that the pots drying to much were a problem (unhappy roots). I have a few pots that hold moister and they have much happier roots.


----------



## Ray (Feb 13, 2013)

OK, so that's semi-hydroponics, only using organic media that will decompose over time.

I am absolutely convinced that the issue is suffocation, not wetness. All of my slippers are in S/H culture (using LECA), stay wet 24/7, and thrive. My longest-term plant grown that way is a Paph Maudiae-type, and it's been constantly wet for 18 years.


----------



## The Orchid Boy (Feb 13, 2013)

Ray said:


> OK, so that's semi-hydroponics, only using organic media that will decompose over time.
> 
> I am absolutely convinced that the issue is suffocation, not wetness. All of my slippers are in S/H culture (using LECA), stay wet 24/7, and thrive. My longest-term plant grown that way is a Paph Maudiae-type, and it's been constantly wet for 18 years.



I'm no expert but, what Ray is saying makes sense. If paphs can live in S/H and be constantly moist/wet in LECA, they could do the same with organic media, as long as there is lots of air available to the roots. The air to water ratio would have to be correct.


----------



## gonewild (Feb 13, 2013)

I said a billion times here.... Orchids grow best if the stay wet. They like their leaves wet they like their roots wet.

You need to have the correct light, temperature and air movement and use a media that does not rot easily and then keeping the plants wet is correct. This requires a dedicated growing area like a greenhouse or grow room, not well adapted to a shelf or windowsill. 

If I have the above environmental conditions set up correctly then I water everyday with nutrient solution. I run intermittent mist that keeps the foliage wet and the media surface wet. Mist comes on as the day starts and ends in time so that the foliage is dry by the time the light goes out.

If you have absolutely perfect environmental control the wet foliage at night is not a problem but that means strong air movement and warm temperature which we really don't like to provide so just dry off plants at night.

My last orchid collection I had in Peru was in a lath house and I ran a mist system in it 24/7. Every hour the mist came on for one minute. Never a rotted plant.

Two major factors to have success with the wet method are use a media that does not rot and use a nutrient solution to feed the plants. Leca is a perfect major component for the media, just mix in some form of organic material to buffer it. Orchid roots need something stable to attach to and decaying bark is not stable where leca is. When you use the inorganic media you need to supply more nutrients.


----------



## eggshells (Feb 13, 2013)

What would be the best temperature for watering? As we know, cold water has more oxygen than warm water but what temp is too cold?


----------



## gonewild (Feb 13, 2013)

eggshells said:


> What would be the best temperature for watering? As we know, cold water has more oxygen than warm water but what temp is too cold?



The best temperature for water is the same as the leaf temperature.


----------



## gonewild (Feb 13, 2013)

I think I tried to argue the benefits of oxygenated water a few months ago in a thread here on ST. 
As I recall I might have lost the argument? :sob:


----------



## NYEric (Feb 13, 2013)

I grow my plants fairly wet. the only problems I have had has been with rotted media and if water sits in the crowns of the leaves.


----------



## Rick (Feb 13, 2013)

Isn't this just resurrecting the TDS monitoring thread I started last summer?

It's not the large amount of water or suffocation that causes root rot but the accumulation of salt by frequent small amounts of water (usually with fertilizer) evaporating in the mix. Salts stay in and build to higher/higher levels with each abreviated watering.

The hotter/dryer it gets the faster this happens.

Also not all "salts" are created equal. Some (like potassium and chloride) are more bioreactive than calcium and sulfate.

Regardless of issues with physiological salt "toxicity", the higher the TDS in the potting mix generates an osmotic gradient making it harder to pull water uphill into the plant during hot/dry times.


----------



## newbud (Feb 13, 2013)

Thanks Rick and all. Good stuff.


----------



## phraggy (Feb 13, 2013)

I water my phrags 24/7 on a drip system with cold water. I use NZ sphagnum mixed with large American sponge rock and only feed twice per year with blood and bone.The roots when first put in this method rot off but are eventually replaced by,what can only be described as thick white hairy rock hard roots.

Ed


----------



## gonewild (Feb 13, 2013)

phraggy said:


> The roots when first put in this method rot off but are eventually replaced by,what can only be described as thick white hairy rock hard roots.
> 
> Ed



Is that good?
oke:


----------



## Ray (Feb 13, 2013)

Rick said:


> t's not the large amount of water or suffocation that causes root rot but the accumulation of salt by frequent small amounts of water (usually with fertilizer) evaporating in the mix.


Not always.

Put a plant in very compact, fresh sphagnum and keep it saturated with pure water. No salts, but the roots will die from suffocation.


----------



## gonewild (Feb 13, 2013)

Ray said:


> Not always.
> 
> Put a plant in very compact, fresh sphagnum and keep it saturated with pure water. No salts, but the roots will die from suffocation.



It might not be either salts or suffocation. It may just be the plant disposing of roots that no longer function in their environment. If a root refuses to pay it's rent the leaves kick it out of the house. 

(Now how am I going to argue this statement?) :evil:


----------



## Stone (Feb 13, 2013)

Rick said:


> Isn't this just resurrecting the TDS monitoring thread I started last summer?
> 
> It's not the large amount of water or suffocation that causes root rot but the accumulation of salt by frequent small amounts of water (usually with fertilizer) evaporating in the mix. Salts stay in and build to higher/higher levels with each abreviated watering.
> 
> ...



All true but the other important point is the supressiveness of certain materials. I had another look at the info in my book. It states that some materials can give 3 years of complete freedom from parasitic fungi attack when added to mixes in as small a quantity as 10%. Some of these include some but not all composted and aged eucalypt barks and other hardwood barks. The suppressiveness of
pine bark is exausted in about 2 months. Thats a huge difference! I think I read some data done in the US on the web but I don't remember the tree sp. that produced similar results. ( a quick search should find it ) The suppression is directly related to the on-going decomposition and the maturity of the material. Apparently the older the better. But any old (several years) organic material (what paphs grow in) will give some measure of control. Those with access to an old growth forest, could gather some old humus from under the leaf litter, screen out the fines and add 10% of that to your mix?
Ok here is some data on this subject
http://www.globalsciencebooks.info/JournalsSup/images/Sample/DSDP_5(SI2)1-11o.pdf


----------



## Stone (Feb 13, 2013)

Ray said:


> Not always.
> 
> Put a plant in very compact, fresh sphagnum and keep it saturated with pure water. No salts, but the roots will die from suffocation.



I agree. Thats why I never use sphag in the mix and why I melt slits in the sides of the pot. Otherwize the only access to air is from the top and bottom of the container and if its in water, only the top.


----------



## Stone (Feb 13, 2013)

gonewild said:


> > I said a billion times here.... Orchids grow best if the stay wet.
> 
> 
> A billion is just not enough!


----------



## gonewild (Feb 13, 2013)

Stone said:


> gonewild said:
> 
> 
> > A billion is just not enough!
> ...


----------



## Eric Muehlbauer (Feb 13, 2013)

I'm not the expert on TDS, I'll leave that discussion to those more qualified. But, I do agree that the issue is more to do with dissolved O2. I think paphs can be really wet, IF they are seriously oxygenated at the roots. I wonder if a "scree" type system, like the ones used by rock gardeners, would work. Constantly wet, but constantly flowing. Sitting paphs in standing water for more than 24-36 hours will invite lots of root rot. On the other hand, I think the reason that phrags like standing water is that their roots seem to be much more tolerant of anaerobic media. I can't believe the number of neglected phrags I've repotted after many years whose mix was just stinky muck, yet the roots were still good and the plants themselves still healthy and growing.


----------



## ehanes7612 (Feb 13, 2013)

Eric Muehlbauer said:


> I'm not the expert on TDS, I'll leave that discussion to those more qualified. But, I do agree that the issue is more to do with dissolved O2. I think paphs can be really wet, IF they are seriously oxygenated at the roots. I wonder if a "scree" type system, like the ones used by rock gardeners, would work. Constantly wet, but constantly flowing. Sitting paphs in standing water for more than 24-36 hours will invite lots of root rot. On the other hand, I think the reason that phrags like standing water is that their roots seem to be much more tolerant of anaerobic media. I can't believe the number of neglected phrags I've repotted after many years whose mix was just stinky muck, yet the roots were still good and the plants themselves still healthy and growing.



its probably both..its like a Eutrophic lake ..which has low Oxygen and high nutrient..and higher acidity ..which i hear is better for phrags (acidity)..than the more alkaline conditions needed for paphs...which as we all know affects nutrient uptake


----------



## wjs2nd (Feb 14, 2013)

Hydroponic growers (not all of them) use a system called, "Deep water systems". A deep water system keeps your plant roots in water 24/7. The waters oxygenated by an air stone connected to an air pump. This keeps the roots oxygenated.


----------



## Rick (Feb 14, 2013)

Stone said:


> All true but the other important point is the supressiveness of certain materials. I had another look at the info in my book. It states that some materials can give 3 years of complete freedom from parasitic fungi attack when added to mixes in as small a quantity as 10%. Some of these include some but not all composted and aged eucalypt barks and other hardwood barks. The suppressiveness of
> pine bark is exausted in about 2 months. Thats a huge difference! I think I read some data done in the US on the web but I don't remember the tree sp. that produced similar results. ( a quick search should find it ) The suppression is directly related to the on-going decomposition and the maturity of the material. Apparently the older the better. But any old (several years) organic material (what paphs grow in) will give some measure of control. Those with access to an old growth forest, could gather some old humus from under the leaf litter, screen out the fines and add 10% of that to your mix?
> Ok here is some data on this subject
> http://www.globalsciencebooks.info/JournalsSup/images/Sample/DSDP_5(SI2)1-11o.pdf



Yup

At what point are we talking wet potted organics versus mounted plants on a piece of bark hosed down on a daily basis?


----------



## phraggy (Feb 14, 2013)

Stone said:


> I agree. Thats why I never use sphag in the mix and why I melt slits in the sides of the pot. Otherwize the only access to air is from the top and bottom of the container and if its in water, only the top.



IMO and a very good friend of mine and I might add one of the finest growers of phrags and paphs in the UK waters his phrags and paphs 24/7 and virtually never repots. I've seen some of his plants almost in mud from the decomposition of the media. He says that the plants grow well because of the incessant clean water they get and also that the fresh water supplies all the oxygen they need. This is why I use his method and you can see the results by the many pics I have posted. The only thing we do differently is that he only foliar feeds with phostrogen.

So there's more than one way of ' skinning the cat '


----------



## Leo Schordje (Feb 14, 2013)

Yikes
I grow indoors, in my basement, under lights. If I misted and watered constantly my little 900 square foot, 100 year old, wood frame house would collapse within a summer from wood rots. I have trouble enough already. Migrating humidity is causing rot on all my window sashes from condensing moisture in winter. I also would not be able to work at all, or leave for trips or take a weekend off. 

I also know my plants do grow better if I am watering twice or even 3 times a week. And I know I run into trouble if I have been watering more often for several months, and then have to let the plants dry out due to travel, or other aspects of living, I loose a lot of plants, the root damage becomes dramatic. My best long term results are to water at a fairly consistent interval, letting plants approach the same level of dryness each time (which means weather wise I might water a day or two earlier if it has been hot and dry). I loose roots and plants when things have to dry out after a long period of consistent watering. So, if I grow continuously on the dry-ish side, there is enough time between having to water, that I can squeeze in a life and not have my home crumble with wood rots from migrating humidity. 

The orchids I grow well, including most Paphs, seem to have adapted to this regime. It may not be fast, I won't tell you I can bloom everything 18 months from flask, but it is a good enough compromise for me. Once a week in winter and about every 4 or 5 days in summer is a workable schedule compromise between me and my plants.


----------



## Leo Schordje (Feb 14, 2013)

Once you set things up, a consistent regime is best. My pot sizes, potting mix, fertilizer program are all chosen to make it possible to do "good enough" on the once every 5 days to 7 days watering cycle. Change one thing and the others have to change.


----------



## Erythrone (Feb 14, 2013)

I discovered that in my growing conditions it is almost imposssible to kill a Phrag because of overwatering. 

But my Paphs must be grown much drier.


----------



## gonewild (Feb 14, 2013)

Yes you have to adjust your watering to match what you can provide. No one wants to rot their house! But the question is under what water conditions do orchids grow best, not will they grow under the conditions you want to or are able to provide.

Start off knowing the perfect conditions and the adapt to that as close as possible.

Using Leo's situation as example he waters as much as possible without destroying his house. Once every 5 days and his plants grow "good enough". That is great but someone wondering how often to water their plants should not assume that orchids should only be watered once a week because that is what Leo does and his plants grow "good enough". If a person can water more often they need to know it is OK, and perhaps even better.


----------



## Rick (Feb 14, 2013)

I have access to a DO (dissolved oxygen) meter, but what is the oxygen condition of concern to test for?

No DO? Low DO? Saturated DO?....

Is Redox (oxidation reduction potential) more important? I've looked at wild rice data and saw that the ORP levels of the generally anaerobic/anoxic (no oxygen) sediments they grow out of make a big difference in performance. The importance of ORP also effects the microbial flora and their actions.

Are you looking for conditions that support the growth of sulfur reducing or methylating bacteria as the primary indicator?

Are we making up science or Scifi on the importance of DO? Or can we even use DO as a cheap surrogate for understanding the stagnant water pot dynamic?

My experience in waste water technologies would say probably not.


----------



## Rick (Feb 14, 2013)

http://www.slippertalk.com/forum/showthread.php?t=27348

Don't forget this thread started by ChrisFL on perspectives of watering.


----------



## Stone (Feb 14, 2013)

Rick said:


> http://www.slippertalk.com/forum/showthread.php?t=27348
> 
> Don't forget this thread started by ChrisFL on perspectives of watering.



Thats not the way to look at it. 3000 divided by 356 = 8.2mm of water each day. Now lets assume they get most of the rain for half the year = 16.4mm of water for each pot to get your 3mt of water per year. You dont have to supply all the empty spaces in your greenhouse to achieve 3mt of water per plant per year.

When I water I usually dip the pots (small pots) in a bucket of water maybe twice maybe three times. Take an average small pot say 70mm deep, every dunk gives it 70mm of water. Thats way more than they get in the habitat.

Its much the same when I use the hose, they get at least the pot volume of water. For a 6'' pot that could be 7 or 8 inches of water every day or two. Tons more water than the plants get (in rainfall) If I gave my plants 16.4mm of water they would not do well. Natural plants don't grow in pots--or you could say their ''pot'' is the entire moutainside-- so with their free root run, they have a continuous supply of water and everything else.


----------



## Stone (Feb 14, 2013)

Rick said:


> Yup
> 
> At what point are we talking wet potted organics versus mounted plants on a piece of bark hosed down on a daily basis?



I don't understand your question


----------



## Ray (Feb 15, 2013)

Just a thought about water oxygen content: the solubility of O2 in water only varies by about 10% over the temperature range we're likely to grow our plants, and will likely saturate quickly in any setup.


----------



## keithrs (Feb 15, 2013)

It has been said by hydro guys that 68 deg f is optimal for o2 saturation and plant growth... You can take a guess at the plants grown.


----------



## keithrs (Feb 15, 2013)

Stone said:


> Thats not the way to look at it. 3000 divided by 356 = 8.2mm of water each day. Now lets assume they get most of the rain for half the year = 16.4mm of water for each pot to get your 3mt of water per year. You dont have to supply all the empty spaces in your greenhouse to achieve 3mt of water per plant per year.
> 
> When I water I usually dip the pots (small pots) in a bucket of water maybe twice maybe three times. Take an average small pot say 70mm deep, every dunk gives it 70mm of water. Thats way more than they get in the habitat.
> 
> Its much the same when I use the hose, they get at least the pot volume of water. For a 6'' pot that could be 7 or 8 inches of water every day or two. Tons more water than the plants get (in rainfall) If I gave my plants 16.4mm of water they would not do well. Natural plants don't grow in pots--or you could say their ''pot'' is the entire moutainside-- so with their free root run, they have a continuous supply of water and everything else.



What is 3000 equal too?


----------



## cnycharles (Feb 15, 2013)

for the example above where you've dunked your plant and say that it's received 70mm of water; it doesn't really compare to the statistics in the wild. in a pot, roots aren't growing in the maximal concentration area for receiving water, and in the wild they are. a tiny bit of water (in the wild) will have more contact as a plant will be growing right where the right water is, and for epiphytic ones the roots are in constant contact with the substrate and where the water will be. also runoff condensation is not accounted for in the rainfall records for an area. 

the wild areas would also never receive 70mm of rainfall in an instant  (though i'm sure some places get a whole lot in a very short period of time, it's just an example that apples need to be compared to apples, not pears)


----------



## Rick (Feb 15, 2013)

Ray said:


> Just a thought about water oxygen content: the solubility of O2 in water only varies by about 10% over the temperature range we're likely to grow our plants, and will likely saturate quickly in any setup.



Yes the saturation of water is temp dependent, but holding temp constant, the amount of water can vary dramitacally based on the chemical or biological oxygen demand.

You can purge O2 out of water with nitrogen, CO, sulfur containing gases.

Add some bisulfite (a common dechlorinating agent) and watch the DO crash in seconds.

Its amazing how little bacteria it takes to cause anoxic conditions with relatively low amounts of nutrients.

Under real stream conditions we can tell how polluted (i.e. "nutrient enriched") a stream is by measuring the diurnal/nocturnal oxygen swings with the battle of photosynthese versus respiration going on. I've seen some badly algae'd up streams go from 2 mg/L DO just prior to sunup (well below saturation, and then clear 14 mg/L DO (supersaturated) just shortly after noon.


----------



## Rick (Feb 15, 2013)

Stone said:


> I don't understand your question



I kind of look at this as a continuum of methods rather that distinct methods.

The most extreme ends of the continuum is mounting (on organic media) at one end with SH using inert materials at the other end.

Baskets, pots of various configuration, potting in various mixes/ratios of inert and organic media just slide up and down that range of extremes, with watering strategies sliding up and down with it.


----------



## gonewild (Feb 15, 2013)

The slow application of rainfall does not really compare to the rapid application of irrigation in a potted plant. Filling a 4 inch deep pot with water and letting it drain out quickly is not the same effective soil moisture as 4 inches of rain over a 24 hour period.

When I reference my continual mist system the "rainfall" measure from the mist is 1 cm per day. That is the standing measure of water (pure) that flows through the pot. This moisture keeps the foliage wet but also flushed through the media. 

Then on top of this amount of water I water the pots with nutrient solution. 
You can't use the measure of water I apply with the nutrient solution to add to the "annual" rainfall comparison because it is basically instant monsoon and then in an instant it is "gone" as far as total water volume.


----------



## Stone (Feb 15, 2013)

cnycharles said:


> > for the example above where you've dunked your plant and say that it's received 70mm of water; it doesn't really compare to the statistics in the wild. in a pot, roots aren't growing in the maximal concentration area for receiving water, and in the wild they are. a tiny bit of water (in the wild) will have more contact as a plant will be growing right where the right water is, and for epiphytic ones the roots are in constant contact with the substrate and where the water will be. also runoff condensation is not accounted for in the rainfall records for an area.
> 
> 
> I obviously didnt make myself clear (my bad!) But thats what I was getting at. Even though the plants are actually getting more water in captivity than rainfall in the habitat, its probably not enough due to the retricted volume of the pot so we need to give much more to make up for the slow and sometimes constant rainfall they would recieve in the habitat and as you mentioned all the runoff. Also, if our water is low in nutrients, (which most are) we need to fertilize at higher concentrations or, preferably, more often at lower rates to make up for all the leaching. The Japanese have a saying when it comes to potted plants: Open mix + lots of water + lots of (meaning consistant) food = better plants.
> If only someone would maufacture a slow release fertilizer with ALL nutrients (not blends) in a larger pill-sized form it would manner from heaven! Just throw some on at the start of the season and then water as much as you like. No more mixing! no more watering cans, no more dipping....


----------



## Stone (Feb 15, 2013)

gonewild said:


> The slow application of rainfall does not really compare to the rapid application of irrigation in a potted plant. Filling a 4 inch deep pot with water and letting it drain out quickly is not the same effective soil moisture as 4 inches of rain over a 24 hour period.
> 
> When I reference my continual mist system the "rainfall" measure from the mist is 1 cm per day. That is the standing measure of water (pure) that flows through the pot. This moisture keeps the foliage wet but also flushed through the media.
> 
> ...



Agreed! Thats why we can't use rainfall figures as a guide to the volume of water we need to apply to the pots or the greenhouse. But we can use the total rainfall data to establish how much water the plant likes (if you follow)


----------



## Rick (Feb 15, 2013)

Stone said:


> Agreed! Thats why we can't use rainfall figures as a guide to the volume of water we need to apply to the pots or the greenhouse. But we can use the total rainfall data to establish how much water the plant likes (if you follow)



How do you get "more" water than standing water in a tray?

If it's there 24/7 you can't get "more" into that tray.

Or did we shift back to watering open pots without sumps?


----------



## Stone (Feb 15, 2013)

Rick said:


> How do you get "more" water than standing water in a tray?
> 
> If it's there 24/7 you can't get "more" into that tray.
> 
> Or did we shift back to watering open pots without sumps?



Both! The plants with sumps get watered just as much as everything else from overhead. The only real difference is that they have constantly wet feet. I'm still feeling my way through this but I put a seedling roth in a water tray a week ago and it already has a root going for an underwater swim. EC of the water is about 0.6 dS/m but this goes up and down a lot. It has osmocote, gypsum, organic pelets and liquid feed now and then but not too much of any.


----------



## Rick (Feb 15, 2013)

Stone said:


> Both! The plants with sumps get watered just as much as everything else from overhead. The only real difference is that they have constantly wet feet. I'm still feeling my way through this but I put a seedling roth in a water tray a week ago and it already has a root going for an underwater swim. EC of the water is about 0.6 dS/m but this goes up and down a lot. It has osmocote, gypsum, organic pelets and liquid feed now and then but not too much of any.



I'm not surprised. I think a lot of paphs could stand a lot more water than we offer.

Can you get a hardness measure of your tray water?


----------



## gonewild (Feb 15, 2013)

Rick said:


> How do you get "more" water than standing water in a tray?
> 
> If it's there 24/7 you can't get "more" into that tray.
> 
> Or did we shift back to watering open pots without sumps?



Standing water in a tray does not compare to water moving down through the media, either in a pot or in nature. 

Standing water in a tray does not address the very (very) important media surface. Letting the surface dry out can delay new rood development. This is especially true with Paphs and Phrags where most new roots start at or above the media level. It may not be "water" on the surface that makes a difference but rather the water dilutes the "salts" that accumulate by evaporation every time the surface dries and moves the salts down and out.


----------



## phraggy (Feb 15, 2013)

I haven't seen anything in the posts that contradict my growing of phrags and paphs indeed all the later posts seem to say that this method is correct!!
I'm thinking that I am very lucky with my water quality--very soft, slightly acid 6.8 .

Ed


----------



## Rick (Feb 15, 2013)

gonewild said:


> Standing water in a tray does not compare to water moving down through the media, either in a pot or in nature.
> 
> Standing water in a tray does not address the very (very) important media surface. Letting the surface dry out can delay new rood development. This is especially true with Paphs and Phrags where most new roots start at or above the media level. It may not be "water" on the surface that makes a difference but rather the water dilutes the "salts" that accumulate by evaporation every time the surface dries and moves the salts down and out.



Generally I agree. It's different for sure. Gravity (water flows downhill) versus capillary action (water wicking in any direction including uphill). But on the side of a tree don't both things happen too?

Plants in pots sitting in trays of water don't have to send roots into the sump to get the water since it will generally travel up to them via wicking action. The fact that orchids are willing to send roots into standing water is more an indication of how wet they can get and still not rot (which I thought was the premise of this thread to start with).

Capillary action is a physical process, so the accumulation of salts on roots or the potting mix surfaces is not mandatory. However, since this is driven partially by evaporation, its easy to accumulate salts on wicking materials. So it helps to keep the sump water low in salts to start with, and still periodically flush out the pot.

I have a good size pot of Phrag caricinum (posted pics a couple years in a row) that is in some kind of clay ball media, and the whole thing sits in a tray of water. For probably at least a couple of years, I used dilute well water with EC about 80uS/cm, but occasionally the straight well water with EC 600. Fertilizing weekly. I used to just let the tray get sucked up by evaporation or plant transpiration and then just top up. Well when I finally got my EC meter, the tray water was well over 1000us. It was probably way higher, but I can't remember now). Anyway, I've been on a heavy duty flush and dump with this pot for months, and it seems to have stabilized at somewhere between 250-350 us/cm. And now it also is pushing some roots out the bottom.

Anyway yes its easy to get out of hand with the tray system if you don't check EC fairly regularly and flush the system periodically. But one advantage, is that you have pool of water in salt equilibrium with the potting mix, so its easy to get a reading whenever you want instead of messing with pour through rates and stuff.


----------



## gonewild (Feb 15, 2013)

Rick said:


> Generally I agree. It's different for sure. Gravity (water flows downhill) versus capillary action (water wicking in any direction including uphill). But on the side of a tree don't both things happen too?



Ummm? on the side of a tree I don't think upward wicking is as prevalent as downward flow. OK ? On the side of a tree does water have the oppertunity to wick upwards? How is the lower part of the tree wetter than the upper. (upper being above the orchid and lower below).



> Plants in pots sitting in trays of water don't have to send roots into the sump to get the water since it will generally travel up to them via wicking action. The fact that orchids are willing to send roots into standing water is more an indication of how wet they can get and still not rot



Absolutely agree I just am saying that even though the plants have roots growing in the bottom water the surface still needs to have a significant amount of water added to have downward flow to constantly replenish the bottom water.



> (which I thought was the premise of this thread to start with).



I don't remember what the premise was! Do we have to have a premise? I hate rules about water!


> Capillary action is a physical process, so the accumulation of salts on roots or the potting mix surfaces is not mandatory. However, since this is driven partially by evaporation, its easy to accumulate salts on wicking materials. So it helps to keep the sump water low in salts to start with, and still periodically flush out the pot.



My focus in my statement was on the surface salts caused by lack of incoming water. I'm thinking of watering applications that mimic natural conditions and wicking upwards is not really natural in most orchid environments. or are they?



> I have a good size pot of Phrag caricinum (posted pics a couple years in a row) that is in some kind of clay ball media, and the whole thing sits in a tray of water. For probably at least a couple of years, I used dilute well water with EC about 80uS/cm, but occasionally the straight well water with EC 600. Fertilizing weekly. I used to just let the tray get sucked up by evaporation or plant transpiration and then just top up. Well when I finally got my EC meter, the tray water was well over 1000us. It was probably way higher, but I can't remember now). Anyway, I've been on a heavy duty flush and dump with this pot for months, and it seems to have stabilized at somewhere between 250-350 us/cm. And now it also is pushing some roots out the bottom.



Exactly my point. water needs to move down from the top frequently, like in constantly.



> Anyway yes its easy to get out of hand with the tray system if you don't check EC fairly regularly and flush the system periodically. But one advantage, is that you have pool of water in salt equilibrium with the potting mix, so its easy to get a reading whenever you want instead of messing with pour through rates and stuff.



Yes agreed. And if you can manage to keep a tiny amount of moisture on the surface at all times you will see an additional improvement in root growth.

I did an experiment with a bunch of kovachi seedlings growing with pots sitting in an inch of water(the same tray and nutrients). Half the plants got mist and half did not. The plants without mist grew mostly roots that went down and into the water. The plants with mist grew roots equally in the water and just under and in the surface moss. The plants with roots growing in the surface moss grew bigger and produced more new growths faster.


----------



## Rick (Feb 16, 2013)

gonewild said:


> My focus in my statement was on the surface salts caused by lack of incoming water. I'm thinking of watering applications that mimic natural conditions and wicking upwards is not really natural in most orchid environments. or are they?



I would say that yes capillary action happens in the wild as well as gravity. The both rules of physics. However the relative degree to which each happens in their respective environments/microhabitats varies dramatically. As long as its raining, gravity predominates. When it stops raining wicking is all you have.

That's why I don't look at this thread as a new different way of growing orchids as opposed to tweaking a management system to adapt to a set of personal growing conditions.


----------



## Stone (Feb 16, 2013)

Rick said:


> > Can you get a hardness measure of your tray water?
> 
> 
> 
> Don't have a clue but there must be plenty of Ca in it. ( but not much carbonate I would guess) I did a little experiment with the Rock Gypsum. I put a few granules into one of those little fert baskets with a spike and put it onto a basket which gets watered most days. The particles were about 3 to 4mm. They were completely disolved away in 4 months. Or at least disolved small enough to fall through the mesh of about 1mm.


----------



## Rick (Feb 17, 2013)

Stone said:


> Rick said:
> 
> 
> > Don't have a clue but there must be plenty of Ca in it. ( but not much carbonate I would guess)
> ...


----------



## Rick (Feb 17, 2013)

http://courses.missouristate.edu/alexanderwait/notes/lecture notes/lecture 11.htm

I've been thinking about this one for a while, but as a question related to the culture aspects of watering.

How does ambient humidity level effect uptake and requirements of fertilizer salts?

One of my earliest "epiphany" moments in orchid culture, was that they need a high humidity environment (independent of watering rates and methods). 

However, I've been able to induce what appears to be symptoms of nutrient deficiency in orchids kept in low humidity conditions (like in my house/windowsills) getting fed at the same rate as those in my high humidity GH.

Another consideration is the amount of light energy required to move nutrients around in a plant. Are the same dry/low light conditions often found for indoor culture conditions able to cause symptoms of nutrient deficiency?


----------



## gonewild (Feb 17, 2013)

Rick said:


> http://courses.missouristate.edu/alexanderwait/notes/lecture notes/lecture 11.htm
> 
> I've been thinking about this one for a while, but as a question related to the culture aspects of watering.
> 
> ...



I'm a little unsure by what you wrote.
You made a "however" statement that has me a little confused, can you clarify if you might have left out a word? I want to make sure I understand your point.

I say once again... orchids grow better with a lot of light and a lot of moisture on the foliage and media surface which comes with higher humidity. 
In low light their pumps run slow and in low moisture conditions there is nothing to pump.


----------



## Rick (Feb 17, 2013)

gonewild said:


> I say once again... orchids grow better with a lot of light and a lot of moisture on the foliage and media surface which comes with higher humidity.
> In low light their pumps run slow and in low moisture conditions there is nothing to pump.



Yup. And if the sump water is high in TDS then the orchids have to pull evaporative losses against an osmotic gradient.

Also the movement of resources through the phloem is an energy requiring process (eating up the sugars the plants are making through photosynthesis).

We've all come up with are zillion ways to skin the same cat. If we are debating what the best way is, I'd say the closest way to mimic nature is the best (i.e frequent rain with very dilute nutrients and high humidity), but that's not to say we can't make other ways work as long as we understand what are the factors that we are compensating for. If that ends up in a labor saving then great. I would also expect a critical review on performance outcomes. Is the plant really bigger/better by the new method, or is it just meeting an already reduced standard that we are satisfied with?


----------



## Rick (Feb 17, 2013)

gonewild said:


> I'm a little unsure by what you wrote.
> You made a "however" statement that has me a little confused, can you clarify if you might have left out a word? I want to make sure I understand your point.



Basically, some orchids I have in low light/low humidity situations are showing symptoms of "malnourishment" although they are getting fed the same rate as plants in high humidity/light conditions fed at the same rate (that are doing great).

I think we've seen this for some of Mutants and Eric M's plants kept indoors under lights/windowsills with less than optimal humidity.

I don't know if SH will work better under these situations or not. Can the plant beat out a humidity deficit by constant wet feet immersion? I attached that link to see if we can figure out what the plants are up against in low humidity/light situations with regard to energy and water balance. At the beginning of this thread, the premiss to consider was "wet feet in and of itself does not cause root rot". Which I tend to agree with, especially with what I've been experiencing with low K low TDS management. 

The thread evolved into another debate on what is the best way to water plants.

Now its pretty obvious that ChrisFl is getting good results with delicate cool growing species with a very sophisticated computer controlled, low nutrient constant rain machine. And Mike is getting some good results with a different group of species in a low tech tray under plant SH method.

So the thread is really to find out why either case works rather than figure out which is better.


----------



## Rick (Feb 19, 2013)

For yet another perspective:

Plants are generally 80-90% water, and 5 or so % carbon.

The NPK.......only acount for about 3 or so % of the total weight of the plant.

So what plants really "feed on" is water and co2 (to make sugars and celulose). 

NPK.... is just to run the machinery of cell metabolism and some cell wall structural integrity.

So you could make the analogy that the NPK..... is really like taking vitamens rather than really eating a meal. Somewhere in our thinking we equated "fertilizer nutrients" as food, and started giving out vitamens as the main "meal" rather than CO2 and water.


----------



## gonewild (Feb 19, 2013)

Rick said:


> For yet another perspective:
> 
> Plants are generally 80-90% water, and 5 or so % carbon.
> 
> ...



That sounds like something I would say to start an argument.
:evil:


----------



## Ray (Feb 19, 2013)

The only thing I take umbrage to is the spelling of "vitamin".


----------



## gonewild (Feb 19, 2013)

Ray said:


> The only thing I take umbrage to is the spelling of "vitamin".



I agree the PC spelling should be vitapersons


----------



## Stone (Feb 20, 2013)

Rick said:


> > So what plants really "feed on" is water and co2 (to make sugars and celulose).
> 
> 
> 
> Don't forget light! without sufficient light they can do nothing with c02 or water or nutrients. Thats why the feeding/watering should follow the light intensity and period. I think feeding tropical plants in a temperate winter is probably counter productive regardless of temps unless you have artificial light. Probably why brachys are so much easier to grow under lights than in a greenhouse where you have to hold them under suspended animation. Not so easy to give them the right quantity of water between totally dry and just barely moist. At least niveum, leuc and godefroyae and thaianum? Thinking about that, why then is exul so easy? (not that I've had it over winter yet)


----------



## Rick (Feb 20, 2013)

http://cdn.intechopen.com/pdfs/3060...ids_current_knowledge_future_perspectives.pdf

Check out this paper, its pretty cool.

Without getting too bogged down on the hardcore physiology stuff, there is some cool ecological stuff mixed in.

Especially interesting to me is the ratio of CAM versus C3 and C4 plants relative to rainfall rates and elevation in the canopy.

There's also a section on productivty/water consumption rates for the different types of orchid metabolism.


----------



## Stone (Feb 21, 2013)

Printing that one..................


----------



## Rick (Feb 21, 2013)

Stone said:


> Printing that one..................



Ya I did too.

I think there's a bunch of good stuff in this article. I haven't finished reading it, and haven't found any references to slippers, but I think a lot of parrallels can be made.

From what I've gleaned so far, that plant photorespiration processes are species specific so you can't generalize "all Catts are...and all Dendros are....all Paphs are....".

So I've been reading this with regard to comparison of habitat differences of say exul versus mastersianum, exposed on a saltwater, bright hot condition (CAM obligate??) versus low light constant dripping wet forest floor (C3 obligate??)

http://images2.wikia.nocookie.net/_...edilum_insigne_and_Paphiopedilum_parishii.pdf

Here's a link to a Paph specific article.


----------

