Pots: transparent vs opaque
 

At a website that sales orchids in Europe I have read that it is preferable the pots to be transparent in order for the roots to get benefit from the light. And that when an orchids stays a lot in an opaque pot will start growing the roots upwards in order to avoid the dark environment of an opaque pot.

I never thought about this issue to play a significant role in the propagation of an orchid and now that I am thinking about it I think that it should be right. In the wild orchids' roots also are exposed to the light and air.

Kept enclosed inside a pot at least I think it would be better if I give them the opportunity to grow with more light reaching their roots.

What do you say about it?

I think you should try it out and be the judge of how you like the orchid's roots are growing compared to when they're grown in an opaque pot... :)

I personally wish I thought of it earlier in my endeavors of orchid growing. It wasn't until I started reading how people on the OB used clear plastic pots to view what was happening to their roots that it dawned on me that not only is that the advantage of orchid growing, but the roots can then photosynthesize. I've got to say I'm very happy with how the roots on my orchids look inside the clear plastic pot versus the ones I pull out of opaque pots.

But then again...

The caveat being that I use them only for epiphytical orchids, not terrestrials whose roots may be photo-sensitive.

Thanks for your thoughts.

Correct, it should be applied on epiphytical orchids.

I have orchids in both types - the upsides to clear having been stated. They do get algae growth inside, especially in plants that are constantly moist

well as king stated with terrestrials you do have some that are sensitive to light in fact a few hardy cyps will suffer greatly from even a minute or two of exposuer to light sometimes even to the point of being killed outright.....

But as far as I know they are the exception not the normal response.

Most epiphytical ones are not going to have a problem and in fact as king said may even photosenthize and in fact some go so far as to have no leaves and the roots do all the work.The ghost orchids for example.

I have noticed that my Catts seem to put roots out to the area of the pot where the light gets to them faster than they do towards the center of the medium where it is basicly dark.

Besides the aesthetically issue is algae harmful for orchids? Btw right now I don't have any orchids that do need tremendously moist soil/bark.

From what I have found the roots of Epiphytic orchids do photosynthesize and is not theory any more.
Quoting from another post:

Quote:

Originally Posted by Ross (Post 123226) Many (not all) orchids have roots capable of carrying out photosynthesis operations. Phalenopsis are a known example. Most the plants capable are also epiphytes (grow on trees or brances). I always see green roots on my phal that is exposed to south-facing window. It is in clear pot, thus the light response. So, yes, this is true. Also consider the leafless species such as the Ghost Orchid that depends on photosynthesis through its roots.

Quote:

Originally Posted by Jadeco (Post 127216) I have recently taken botany, and our textbook (Introductory Plant Biology by Kingsley R Stern, James Bidlack, and Shelley Jansky) pointed out that, initially, the primary function of phalaenopsis orchid roots was believed to hold water since their roots are so thick, but recent research has shown that they heavily involve photosynthesis. I wish I still had the textbook to cite any sources and give exact quotes.

and a couple of links I have found:
link 1, link 2

Is this true? (I hope so) since I have a Bulbophyllum with 6 p/b that has lost all leaves but one. I had some thoughts regarding the role of the leaves so I asked in a Greek forum about orchids. A member there said that the leaves hold water and an orchid can live without roots but can't survive without leaves.
Now that you've said that, I have googled the ghost orchids, saw the images and I don't know what to believe. Maybe the ghost orchids are so unique and different and they don't need leaves?
Really I have no idea.

Yeah!! exactly mine has done so! Basically my Cattleya warneri is young with 4+1 new p/b but has grown a couple of big and thick roots very distant from the base of the p/b.

as far as I know - algae does not harm the plants. But I do have pots with quite a bit of algae growth and it just negates the ability to monitor root growth.

That then should be too moist and kept for many months like that :shock:

I have algae growing in the clear plastic pots with the orchids, and algae growing on the mounts that I have my orchids on. No problems have been detected whatsoever.

This is great information. I love it when everything comes together.

To be scientifically accurate (forgive the nerd moment), the fact that it is now known that epiphytical orchid roots have photosynthetic capabilities and is heralded as being true, IS theory.

The actual true meaning of theory versus the colloquial (aka everyday speech) meaning of the word is that the idea, concept, or phenomena has truth, and that it's very difficult to discount because a lot of things support it. Theories can be and sometimes are amended to more accurately capture the truth of what is being described.

Whereas, when the idea of orchid roots having full photosynthetic capabilities was still in question, it would be regarded as being hypothetical.

I wanted to sort this out just in case there was any kind of confusion amongst different groups of people.

Bulbophyllums are a whole different story. If you've lost the leaves, but the pseudobulbs are intact and are not rotting and it still has good roots, it may bounce back. It's difficult for it to, but it still has a chance.

If the leaves on many, if not all the pseudobulbs have dropped, and if there are a few pseudobulbs that have rotted away, along with many of the roots; needless to say there is a problem. The ability of the Bulbo to bounce back in this scenario is greatly diminished and also depends on how big and strong the remaining pseudobulbs are, and whether there are enough good roots along the rhizomes to do it (if I had to give you a number, I'd say no less than 5 pseudobulbs ideally).

Sometimes, new growths on Bulbos will come out from the living and healthy portion of the rhizome itself. But in order for this to happen, there usually has to be enough big strong healthy pseudobulbs that are alive to support this kind of comeback.

Even if the rhizome doesn't have roots, as long as it's alive and healthy with enough strong and healthy pseudobulbs to support it, new growths will come out of them.

If neither rhizome nor roots are alive, needless to say, nothing's going to grow out of it.

This seems complicated, and I'll admit, it's complicated to describe in words. When it happens you'll know what I mean.

I'll be more specific and use genus names rather than common names for reference about this particular topic.

There are actually quite a number of epiphytical orchids that have either diminutive, vestigial, or full blown leaves with extremely limited photosynthetic capabilities. It really depends on what you're talking about.

Polyrrhiza is just one group of "leafless" orchids. Another are Chiloschista spp. There are also plants such as Taeniophyllums, Dendrophyllax, and Harisella.

All the orchids mentioned above have roots that are capable of full blown photosynthesis. They may also produce leaves, but like I said they are rudimentary generally speaking. I suggest you read up on this, it's very interesting.

However, some Phalaenopsis behave in a similar (note: the word "similar" has a different meaning from the word "same", similar means it's close in proximity but not identical; I understand that in everyday speech we sometimes interchange these two words with each other when they actually have very subtle differences in meanings) manner to the "leafless" orchids. Phal braceana is one. I like to collectively call these unique group of Phals the deciduous ones. They behave a bit differently than the more commonly grown evergreen Phals.

In fact, many Phalaenopsis can bounce back from "near death" if the roots are strong and intact but the leaves are completely gone. I have had it happen to me, so I know for a fact, it can happen.

I wanted to post this separately because this is a bit off topic.

If you didn't know this already. And I know some of you OB members out there already know this...but this one's for those who don't know.

Some orchids have extremely limited photosynthetic capabilities or do not photosynthesize at all. For these plants, photosynthesis is not the primary means of gathering the energy and food they need to survive. Many of these are the ones that are not in cultivation, and will probably never be. Or...if they are in cultivation...no one has stepped up and disclosed any successful long term methods for cultivation.

These orchids are usually terrestrial and usually form such a tight and unique symbiotic relationship with fungi and other plants, that it would be extemely difficult to replicate such an environment artificially.

These are either mycotrophic, saprophytic or a combination of both.

One example of these are Corallorhiza spp. Some others are Neottia nidus-avis and Rhizanthella spp.

Just my two cents:

While the roots of epiphytic orchids have the ability to photosynthesize, I'm not convinced that clear pots translate to better root growth due to increased photosynthetic activity. It's possible, but I'm a skeptic.

I understand how in nature, the roots may dangle in the open air and receive ample light. But not all of the roots receive light, and some are so crowded and shaded by ferns, broms, moss, algae, etc. that the roots exist in near darkness - like an opaque pot. I've had plants that love to put out aerial roots, and some that grow right down into the pot. Opacity of the pot has never been a factor, and I get Cats to fill both kinds of pots with roots (usually down near the bottom). Also, some propagators have described a benefit from a darkened medium and found that epihpytic orchid roots sought out an opaque medium more readily than the same medium minus the dye, stain, or charcoal. I'm not sure I buy into this anecdotal argument either, but it would seem to contradict a benefit from root light exposure.

Having said all that, I do prefer clear pots. :) Being able to monitor root growth, and more importantly moisture level and media, has improved my culture which, in turn, has improved my root growth. Again, I may be wrong, but I believe that we would be taking a leap by confusing the ability to photosynthesize with a preference for it.

Perhaps I should've been more specific or clearer in my statements.

I'm merely speaking in terms aesthetics, not how fast the roots grow in a clear pot due to photosynthetic activity versus in an opaque pot and non-photosynthetic activity.

They just look better. I like how they're green underneath the silvery white velamen instead of translucent white. I find the root tips to look more attractive with the range of colors they produce due to their photosynthetic behaviors.

The roots appear more vibrant to me.

Because they're easier to see, proper root maintenance is easier. Therefore increasing the chances of a healthier looking root system.

I really can't say whether the roots are growing faster because of the ability to photosynthesize. I don't have the resources nor time to conduct an experiment to detail this question out.

It would be interesting to know though. :)

But...

If it can photosynthesize why not allow them to? I don't see where it could hurt. It obviously helps out to some degree. To what degree, I currently have no idea (speaking in terms of quantifiable data and results here).

An epiphytical orchid's ability to have it's roots perform photosynthetic activities when it's exposed to light and have those roots that are not exposed to light perform another duty fit for it's survival is ingenious. The most expansive portion of an orchid's anatomy are not the flowers, seed pods, leaves, stems, rhizomes, or pseudobulbs, it's actually the root system. It appears to be an adaptive trait to maximize the use of whatever sunlight is available to them in the area. Particularly when many epiphytical orchids grow under the canopies of trees.

This is the stance I'm taking.

This is the only point I intended to make. I am all for good root growth, and I like clear pots. I just didn't want anyone to read this thread and assume that it is a known fact that more light to the roots = better root growth. As illustrated in the "just add ice" threads, people have all sorts of variables in their conditions that make these observations just that, observations. They may be correct, but there is still much that is not fully understood about the roots of epiphytic orchids.

Understood brother bear. Understood.

This thread became very informative http://www.orchidboard.com/community...ons/icon14.gif

As for the theory or not about the photosynthesize of the roots or part of the roots in Epiphytic orchids, from the investigation that I have provided (links at the 1st page), there has been biological research regarding this issue, therefore I believe it's not theory any more and it's a fact.

It would be theory if there wouldn't have been any investigation and there haven't published any positive results.

As for the choice that people will make, clearly as you also mentioned, each one has his own thinking, needs etc.

As for me I will replace with clear transparent pots (not those semi-transparent ones I have seen) in all of my epiphytic orchids.

In my thinking about correct propagation of orchids what comes first is if I can achieve the similarity of the growing conditions in the wild AND the ease of care for me, so that I will not find one day that I live and breathe for my orchids and not for myself :biggrin:

Therefore my conclusion is that I will go for the clear transparent pots for all reasons mentioned here AND to help the plants photosynthesize better. I have read the findings and personally I am convinced.

Thank you all for your insightful contribution. I believe our epiphytic orchids are more pleased right now.
:D

This is a good point. :lol: