Physan 20 and flower spikes

[richardb]

That is useful, Howard. Just had a quick look at the internet and the product looks similar to some others we are researching whose main use is disinfection of medical and kitchen areas. I'll look at it further.
Either way, for us over here it is "PHYSAN 20 - our loyal friend R.I.P"!
Richard

[got ants]

I was at the Davie Orchid Societie's monthly meet in February and the speaker praised Physan 20 big time. But he specifically warned against spraying dendrobiums with it.

I have not yet used it but I use 2 different fungicdes on my chids, DITHANE M-45, and THIOMYL. The Thiomyl being a systemic, and Dithane topical.

Now I'm wondering if the white spotting on my Dendrobium Aggregetums. These spottings are almost the whole leaf on top turning whitish pale colour.

Also have some leaf loss on my cane Dendros, and possibly caused by the fungicide treatments.

So now I only mix small batches for my Onciciums and phals. Haven't had any problems with my catts, so they aren't being treated either.

Again, I'm not sure, just going on what I have recently heard....

[Pazuzu]

Originally Posted by richardb

No bruised toes nor bleeding nose. I guess that is what makes orchid growing so interesting that there are as many opinions as there are growers. Most interested to hear that Physan on flowers is OK for some............I guess I shall no longer have the chance to experiment spraying my flowers with Physan again. My search for an alternative in the UK continues.
Richard

I have just started my search for Physan 20 substitutes in the UK. so far I have found this :-

Buy C10-C16 Alkyl Dimethyl Benzyl Ammonium Chloride - BAC 50 Online at MistralNI

I hope this is helpful. If you have any other recommendations for fungicides suitable for dipping my nearly dead Cymbidium backbulbs prior to trying to get them back into growth I would be pleased to hear them.

[Ray]

I have used Physan @ 1 teaspoon per gallon as an algae preventive measure for years, and have rarely seen any issues.

I have recently changed to a broad-spectrum algaecide/fungicide called Zero-tol, which is a peroxyacetic acid-stabilized hydrogen peroxide product, and it has no phytotoxicity whatsoever. About a month ago I sprayed the entire greenhouse - glazing, benches, floors, plants - even some in spike and bloom. In 5 minutes that algae was white (and flakes off when dry) and nothing at all happened to the plants.

[silken]

We can't get any Physan or similar products in Canada either. It's been that way for a while. I will have to see if the Zero-tol can be found. If anyone knows of something available it Canada it would be nice to hear what it is. My weapons are listerine and sulfur powder!

[Pazuzu]

I looked up benzalkonium chloride Canada on google & it looks as though the chemical is licenced so I would guess that products may be available on the shelf. It is a constituent of several household disinfectants in the U.K but I am not sure what the surfactants, perfumes & limoline also featuring on the ingerdients list would do to my already borderline cymbidium backbulbs !!