Plants to keep away from Phyton 27?

[TOMMYMIAMI]

I just wanted to ask about physan 20, first is this one safe for all the orchids, even Dendrobiums? Second, do you use it as a prevention (mixed with fertilizer) or only as a treatment? Many thanks, I have never used anything like this.

[NYCorchidman]

Originally Posted by TOMMYMIAMI

I just wanted to ask about physan 20, first is this one safe for all the orchids, even Dendrobiums? Second, do you use it as a prevention (mixed with fertilizer) or only as a treatment? Many thanks, I have never used anything like this.

Physan 20 is sort of like Clorox that clean out the surface spores from what I understand.
I have used it on oncidiums for spotty leaves and had mixed results.
I no longer use it. I am scared of chemicals.

It shouldn't affect dendrobiums negatively as long as you follow the correct dilution instruction, but if you value highly of your dendrobiums, I would test on one leaf first to see any bad reactions.

You don't mix it with fertilizer.
Physan 20 is not absorbed into the plant like phyton 27.
The label of physan 20 does mention using it as a preventive measure, but honestly, unless you are a professional grower with thousands of crops that you don't want to risk losing big money out of, I don't think it is worth it.
Also, as I mentioned above, I personally did not see much benefit using it.
I read that physan 20 can strip off the protective outer layer of the plant leaf. I don't know if this is true but some of my plants still developed fungal spots after being treated with physan 20. it may or may not be related to the use of physan 20, but again since I did not see satisfactory result using it, I no longer use it.

Is your dendrobium having issues??

Usually, proper care prevents most problems.
then when something does happen, you can cut off the affected area early on. that's usually the end of it.
Any recurring disease, you either spray or toss the plant if that is an option.