Curious Cattleya Roots

[tucker85]

Aerial roots are physically different from roots growing in the medium. They have more velamen which is the white coating on the root. The velamen helps the orchid absorb moisture from the air. I have noticed that some nutrients and suppliments make the roots even whiter. I started using liquid seaweed on my plants and they developed very shiney almost flouresant white roots. Be careful with that sphagnum moss. It retains a lot of moisture and Catts like to dry out. Good luck.

[goodgollymissmolly]

Cattleya roots are white with green or reddish brown growing tips depending on the species or the background of hybrids. They do turn green with watering but it takes a good bit of watering to do it. They first get a variegated look.

Each new Cattleya growth should be larger than the previous one....if not you are doing something wrong.

And, no, roots are roots. There is no difference between those in the pot and those that are "aerial". They may look different due to coloring but they are not. That's an internet myth passed down as fact.

[tucker85]

On page 84 of William Cullina's excellent book "Understanding Orchids", under the heading "Attaching the Orchid" you will find a discription of the difference between roots that grow in medium and those that grow in air. If you don't have the book you can actually read it online through Google Books. Good luck.

[Melody]

Ok, so how do I improve the conditions for this guy so his next growth is back to being big and happy?

I've had this plant for 4 1/2 months. It was out of bloom and I have not repotted it. The center is 100% bark then there is about 2 in. of spag that lines the edge in between the bark and the pot. When I got it there wasn't any roots in the spag, but the new roots are growing into it.
I keep it in a North facing window and water about once every 2 wks because it seems to take forever to dry out. I've been fertilizing every other watering. Humidity is only about 46 where it is currently.

I can hear the thinking now "All wrong, do it over" <- that's a quote from one of my prof. it always made me laugh even though he was serious

[tucker85]

Here's a link to the AOS culture sheet for Cattleyas.
AOS | Cattleya

And here's a video on repotting catts. I hope the link will work.

YouTube - Repotting a Cattleya

[goodgollymissmolly]

Tucker, I would avoid disparaging my orchid library or my knowledge of its content until you know better. If you wish I can post the entire content of the library along with photographs. I assure you it's a substantial library as private ones go.

As to Mr. Cullina's book, it is the book that I recommend to every new grower. In my opinion it's the best general orchid book available. That doesn't mean that I agree with every word and I do not agree with the part you pointed out for a simple reason that I'll describe.

Mr. Cullina makes two statements...one that orchids have two types of roots, one in the pot and one out of the pot......and two, that these two types are not convertible.

Both of those statements cannot possibly be true. Anyone who observes the production of new Cattleya roots can easily see that only a single type of root grows from the base of a new growth...a white, velamin covered root with a green or reddish growing tip. The plant clearly does not produce two types of roots and there is no evolutionary reason it should.

So...either all the roots are the same...or some of the roots are converted to another type (the in-pot type) after entering the medium. Take your pick but one of Mr. Cullina's statements is wrong via common sense reasoning.

The fact seems to me to be that the roots that enter the medium are deprived of light and experience more moisture than a root not in the medium. As a result the root reduces its moisture storage capability by reducing the velamin layer and produces fewer chloroplasts (green) in the root cells because they are not useful in the dark. (The same thing occurs in reverse in the leaves based on light levels. High light fewer chloroplasts, light green to yellow foliage). Thus you see a finer root with less green when you uncover the root. I believe that root will eventually return to the other (and only type) appearance if removed from the moist/dark and given time to change. This experiment is difficult to perform because Cattleya roots are not long lived with only two to three years growths having live roots attached.

There is no indication that the plant produces two types of roots initially, nor that it should. How would the plant even know that a pot was available? After all that's a pretty unnatural thing to an epiphyte. It's just one of our artificial ways to grow the thing in captivity. It's unlikely the plant anticipated being in captivity. don't you think?

[CTB]

[QUOTE=tucker85;361066]Aerial roots are physically different from roots growing in the medium. They have more velamen which is the white coating on the root. The velamen helps the orchid absorb moisture from the air. QUOTE]

I agree Tuck, they adapt themselves quite differently. This book is a good addition to anyone's library. Thanks for the video, I watch the repot me video and hadn't thought of you tube.

[tucker85]

Goodgollymissmolly, I apologize for upsetting you. I was only trying to help. From now on I think I will refrain from giving any advice or opinions. I will leave that up to those more knowlegable like yourself. I hope you have a wonderful Thanksgiving week.

[BobInBonita]

Tuck and GoodGolly
As a relatively new participant here, I value your posts - please don't refrain from offering opinions.

I was disturbed by the direction of this and a couple of other posts (by other authors) recently.

What makes Orchidboard great is that people actually seem to leave ego out of it.

In many threads you can see different sides to the same question. Users can pick what fits their growing style and philosophy.

It seems lately that more folks (not just in this thread) are pushing "my way is right", which is probably the only wrong approach.

If Orchidboard goes that way, it will become like so much of the internet - a place for quick confrontation and extreme views.

Please don't stop posting, but please leave the door wide for alternative approaches. We all learn most by comparing and trying different things, not by following one style blindly. When territorial marking starts, communication stops.

Thanks for letting me vent, and hope this doesn't offend either of you.

[Melody]

BobInBonita,
Thanks for your post. I agree completely.

This board should be a safe place for people to post their thoughts and ideas without the fear of being attacked. I created this thread because I value ALL member's opinions and am a bit saddened that this thread has gotten a bit off topic.
So....
The current topic of this thread should be: Everything I'm doing wrong and how to fix it. hahaha...