Loss of roots of phalaenopsis when there is change of substrate
 

Hello everyone. I need advice to keep the roots of the phals from dying when I change the sphagnum moss by bark. Usually my phals lose many roots in this process and many times they are left without any. What I can do?

Nothing, but be aware of that, and prepare for it.

When roots grow, they "tailor" themselves on a cellular level to the environment into which they are growing. When that environment changes, either due to repotting or the decomposition of the medium, or even a change in watering habits, those roots are no longer optimal for that new environment, so will fail.

That is why it is always best to repot just as new roots are emerging from the base of the plant. Those new roots will grow optimized for THAT environment and support the plant, as the old ones fail.

Ray omitted a piece of information which I'm going to add. I think his omission was because he's not trying to sell you anything, but I'd like to recommend using a product he sells. KelpMax. For a long time I avoided using it, though I have no idea of why. Several months ago, though, I bought a bottle. In a relatively short time using it, my healthy, well-rooted orchids have become root-growing machines. My belief is that maintaining the roots is what allows the plant to grow and absorb nutrients, and the healthier, more vigorous plants are what lead to the most brilliant, showy flowers. No, Ray doesn't kick anything my way for saying this, and no, I don't do testimonials. However, if you want good roots then Ray's KelpMax is, I've quickly learned, probably the single best product to get them. It's not inexpensive as fertilizing products go but now that I've used it I would pay twice the price if I had to. (Ray, we need to discuss that kickback, right? After all....) Also, I'll go out on a limb and project that with regular KelpMax use, repotting from one medium to another will allow the roots a much better survival.

Thanks, John. Check is in the mail....

A couple more things I forgot to mention:

The greater the degree of difference between old-, and new root zone conditions, the faster and more complete that loss of old roots will occur.

Another is that sometimes, the move from one medium to another is a step in the right direction. That seems to be more common on the switch from soppy moss to semi-hydroponics, and I speculate that's because, while they're both wet environments, the latter still allows the roots to "breathe".

Thank you very much. I thought that but I hoped to be wrong. Anyway I feel happy knowing the existence of Kelpmax and I will buy it as fast as I can, thank you all for your help, regards

Another doubt, when the roots begin to deteriorate, then you have to remove the plant again and cut those roots?

In my experience, that depends upon the degree of difference in conditions, the extent of the failing root system, and the potting medium.

For example, for a plant with a moderate root system moved into a good, open medium, as they fail and decompose, they release nutrients and the broken-down bits are flushed away with good watering. If, on the other hand, the system was extensive, and/or it all dies at once, and/or the medium does not freely flush (sphagnum), it may require unpotting and repotting to get rid of the "cesspool" it has created. In those circumstances, I trim the old roots before repotting - another reason to make sure there are new roots emerging.

I already have the kelpmax from First Ray, this weekend I will start watering my orchids. I would like someone to tell me which is the physan 20 fungicide that is bought for orchids because I see 2 different bottles, thank you all for your help.Regards.

I don't use fungicide unless I have a known fungus problem, I know the fungus, and I am certain the fungicide I have treats the fungus causing the problem.

Plants usually have beneficial fungus and bacteria growing on them that keep the pathogens in check. Indiscriminate use of fungicides promotes growth of harmful organisms when beneficial organisms are killed.

I realize many respected growers in Florida treat plants with fungicides on a regular basis during periods of very high humidity. Is your relative humidity this time of year constantly over 60%? If it is not, I would only use fungicides if a problem occurs.

Thank you very much. I see that when there are problems of crown rot or roots, they use the physan 20 and I am changing the substrate of some phals that buy in moss, for bark, as you always know they are many rooting roots and I do not have any fungicide that's why I ask. My relative humidity at this time is not constant, some days is too high and others too dow. Regards.