Watering

[Stone]

What aproach do you take with regards to watering?
I'm still not 100% sure but I think I've noticed the following phenomenon:
I have been watering my seedlings in the normal way, that is: soaking the pots and waiting for them to dry a little then repeating etc., and they plod along as normal, putting out a new leaf here or a new root there.
But after a month or so of this sequence, if I really flood them for 2-3 days in a row, they seem to be greatly stimulated into faster more vigourous growth
for a while with more root initials breaking at their bases.
I wonder if it's a natural adaptation to coincide with monsoonal downpoors?
I try to time this ''flooding'' with a warm weather forecast. I think there might be something in it?
Anyone else observed this? or am I watering incorrectly?

 

[cnycharles]

interesting observation. quick answer is I don't know, would depend on what you were watering and all the rest of your environmental conditions, and the state of your bark/media. if you have fresh bark, often it will dry out more quickly and maybe keep your humidity higher. would be nice to know if it was due to monsoonal influence

 

[Stone]

I'm not a huge fan of bark but I do use it as part of a seedling mix.
The bark we get here is Pinus radiata. It is always comosted with lime, urea
and iron suphate for a few weeks and ends up black and slightly water
absorbant. I always wash it before using it to get rid ofthe dust but it still holds a fair amount of moisture. I like the pots to dry fairly quickly (2-4 days)
so I use a course grade 1/4'' mixed with porous volcanic rock and coco husk of same size.
I still have the eternal problem of the top drying too quickly and the bottom too slowly so I've been adding a finer material on top but that kind of defeats the purpose. That's why I think mesh pots and baskets are a possible solution-- fine material on top for the base of the plant and no need to worry too much about over-watering.

 

[Ray]

I'll bet that if you flushed heavily at every watering, you'd see overall better growth.

Waste products accumulate in the medium, resulting in - to a small degree, at first - the plant sitting in its own cesspool. if you flush heavily and frequently, the root environment stays cleaner and healthier.

I use Orchiata bark (when I use bark) - it's the treated Pinus radiata coming out of New Zealand - and by using a coarser grade, coupled with frequent heavy watering, I see great growth in it.

 

[keithrs]

I just switch some denenatii from pine seedling bark into orchiata classic with small amount of moss and green sand..... excellent results....Or should I say excellent response. Mist very morning and evening, water very other day or two.

When I water, I use a misting nozzle for three reasons...
1. Not to disturb the seedings
2. Allow the bark mix and roots to absorb water
3. Not to waste too much water

I just about killed them all, Between staying to moist and physan. I did lose about half because of the physan dried out the roots and pitted the leaves.

I used dried green moss to hold the sand in the pots. The sand was used for the root hair to attach to and get some trace minerals. The bark is basically there for humidity at this point. I fertilize every other watering.

Live to learn... right!

 

[gonewild]

What you are seeing is not a seasonal responce. If you install a automatic misting system and keep the surface of the media moist at all times you will see that the plants grow faster more have vigourous growth than letting them dry out between waterings.

 

[Stone]

I'll bet that if you flushed heavily at every watering, you'd see overall better growth.

Waste products accumulate in the medium, resulting in - to a small degree, at first - the plant sitting in its own cesspool. if you flush heavily and frequently, the root environment stays cleaner and healthier.

I use Orchiata bark (when I use bark) - it's the treated Pinus radiata coming out of New Zealand - and by using a coarser grade, coupled with frequent heavy watering, I see great growth in it.

I flush heavily at every watering and before feeding

 

[Stone]

What you are seeing is not a seasonal responce. If you install a automatic misting system and keep the surface of the media moist at all times you will see that the plants grow faster more have vigourous growth than letting them dry out between waterings.

If I did that my plants would rot real quick!

 

[keithrs]

If I did that my plants would rot real quick!

You need move air movement.

 

[Stone]

You need move air movement.

I have 4 fans blowing 24/7 plus an industrial evap.cooler on a thermostat.
I don't need more air movement.
I must say I disagree with Lance about the need for a misting system. I believe that allowing them to dry out '' a little'' between waterings is only following a natural cycle that ALL tropical plants have evolved with. Epyphites all the more so but even ground dwellers. I have observed this first hand in Nth. Queensland rainforest where everything including mosses on the ground are can be crispy-dry in a matter of days after rain and during the wet season, yet the area still supports many orchids.
Some of our club members noticed a similar thing on a visit to the sanderianum habitat in Borneo.
I do have a misting bed which I use for propagation and it can help with getting things moving but long-term use would surely see things go down hill.
I still believe that letting them dry out over an extended period followed by a short period of ''soaking to the bone'', stimulates them more than usual

 

[gonewild]

If I did that my plants would rot real quick!

That's only because you have conditioned them to growing in a drier environment. They should not rot "real quick" from being wet if the environment around them is correct.

 

[Stone]

That's only because you have conditioned them to growing in a drier environment. They should not rot "real quick" from being wet if the environment around them is correct.

What do you consider to be a ''correct'' environment?

 

[gonewild]

I have 4 fans blowing 24/7 plus an industrial evap.cooler on a thermostat.
I don't need more air movement.
I must say I disagree with Lance about the need for a misting system.

I did not say you need a mist system. I said if you had a mist system you would see the constant growth that you now notice as spurts of growth after your water them extra. I'm not disagreeing with you about your observations.

I believe that allowing them to dry out '' a little'' between waterings is only following a natural cycle that ALL tropical plants have evolved with.

Not ALL tropical plants plants have evolved with the same wet/dry cycles. Most often the dry cycles run for a lot longer than you would dare allow a potted plant to remain dry. You can also consider that the natural conditions are not perfect just because a species has evolved to survive in the conditions. Most people want their plants in their collections to look a lot better than wild plants. Under the natural conditions of the tropics very few plants survive for very long so growers should look for ways to improve on Nature and not simply try to mimic it.

Epyphites all the more so but even ground dwellers. I have observed this first hand in Nth. Queensland rainforest where everything including mosses on the ground are can be crispy-dry in a matter of days after rain and during the wet season, yet the area still supports many orchids.
Some of our club members noticed a similar thing on a visit to the sanderianum habitat in Borneo.

Correct, the habitats dry out. But does that mean that drying out is the best thing for the plants to grow better? Or is that a method that Nature uses to inhibit the growth of plants to keep them under control so they don't grow too much?

I do have a misting bed which I use for propagation and it can help with getting things moving but long-term use would surely see things go down hill.

Have you tried long term growing under a mist to see the effect first hand?

I still believe that letting them dry out over an extended period followed by a short period of ''soaking to the bone'', stimulates them more than usual

Maybe this is because the plant finally has a chance to grow after surviving the drought?

 

[Stone]

I did not say you need a mist system. I said if you had a mist system you would see the constant growth that you now notice as spurts of growth after your water them extra. I'm not disagreeing with you about your observations.



Not ALL tropical plants plants have evolved with the same wet/dry cycles. Most often the dry cycles run for a lot longer than you would dare allow a potted plant to remain dry. You can also consider that the natural conditions are not perfect just because a species has evolved to survive in the conditions. Most people want their plants in their collections to look a lot better than wild plants. Under the natural conditions of the tropics very few plants survive for very long so growers should look for ways to improve on Nature and not simply try to mimic it.



Correct, the habitats dry out. But does that mean that drying out is the best thing for the plants to grow better? Or is that a method that Nature uses to inhibit the growth of plants to keep them under control so they don't grow too much?



Have you tried long term growing under a mist to see the effect first hand?



Maybe this is because the plant finally has a chance to grow after surviving the drought?

When I say 'dry out'' I mean holding them slightly moist then flooding, not desication. I don't subject them to drought.
Plants evolve to thrive not just survive in a given environment. After all they have had millions of years to get it right.
Through human eyes they may appear ratty and beaten up but they are usually perfectly healthy. Probably more so than our often bloated over-fed captives. Your statement that very few plants in the tropics live very long is-
I believe- just not correct. Orchids growing on 300 year old trees just keep growing unless they get eaten or fall off. There are early records of Vandas estimated to be upwards of 100 years old and I've seen dendrobiums that would have to be at least 50.
Nature dosen't have a ''method'' to keep growth under control, It just is what it is. You can't seperate it's components. But you've given me food for thought and I might experiment with keeping some wetter to see what happens. Thanks for your input

 

[keithrs]

My seedling stay moist at the roots..... I switched two a courser grade bark to get more air movement around the roots. I have since had new leaves and roots start. Dead roots from physan use I believe is what was causing the rot problems.... Water its shelf will not cause rot..... it the bacteria and viruses that breed in moist conditions that don't have enough air movement that cause rot on roots and leaves. I only have one 8" oscillating fan on low at all times for my bakers rack and one computer fan for each of my domes that have my new seedlings and have have zero problem in the last two months.... I really contribute all my problems to physan. I fact I have only lost 4 plants that didn't get a Physan bath. More than half die with the bath.

 

[keithrs]

May be you can try repotting a few in your mix without the finer stuff on top and try the misting ways..... Never hurts to try a new way!

 

[Stone]

All I'm saying is that for many other orchids that I grow, I can get a quicker initiaion of new roots when I withold water for a time and I'm seeing the same thing with paphs. Although I still have a lot to learn about them.

 

[Rick]

All I'm saying is that for many other orchids that I grow, I can get a quicker initiaion of new roots when I withold water for a time and I'm seeing the same thing with paphs. Although I still have a lot to learn about them.

C

Could just be coincidence in timing of water rather than induced root production by watering.

I've noticed that many of my paphs bloom, develop roots, flower, add new growths at different but predictable times of years.

Also it may be hard to generalize about all paphs given ~80 species in 6 or so significant subgenera, utilizing fairly distinct habitat types from limestone cliffs to deep forest duff.

You seem to be interested in Paph habitat info for insight for growing. You should get Averyanov's book on Slipper orchids of Vietnam, and Lance Birks Paphiopedilum Growers Manual. Both have climate and habitat info. Averyanov's book is particularly detailed in this respect.

 

[Rick]

Actually I'm surprised that Ray didn't bring up the results of SH growers that seem to have no problem growing roots with some of them constantly submerged in water.

I use SH for a lot of my phrags. Some have been in the same matrix (hydroton balls) for almost 10 years now. Sometime I let the pans dry out, but often there is water in the pot for weeks on end (with flushing). Roots coming out of the bottom of the pot would tell me that at least some of these roots are almost constantly submerged.

I did have decent luck growing Paph tigrinum SH, and they also developed roots that stayed submerged. (I moved them to baskets though and they are doing even better).

I can't recall who it was, but someone on this site (I think from Canada) was growing P. belatulum SH and had amazing roots (some constantly submerged).

 

[Stone]

Yes Rick I have Lance Birk's book and looking forward to getting Averyanov's.
I've also noticed that some roots can survive totally submerged in water as long as the bulk of them is above it. They must be supplying air to the bottom ones? I have a feeling that totally submerged is different to constantly wet. Possibly because the submerged roots are not subject to attack by aerobic pathogens?
And yeah I saw that bellatulum--amazing!