anti-fungus spray - Orchid Board

calypsoB · #1 06-04-2011, 12:51 AM

ok, so I have this anti fungus spray that I beleive is mainly thyme oil an it kills 99% of fungus and bacteria. My question is- Is it safe to use on or near an orchid?

OrchidThief79 · #2 06-04-2011, 01:16 AM

I've been investigating fungicides a lot recently. The main fungicides used on orchids are Physan, neem, copper compounds, and a variety of chemicals such as mancozeb and thiophanate methyl. I haven't heard of using thyme, but I can't imagine that it would be harmful at all given that humans eat it. The only fungicide that can be harmful to orchids is copper, and that's only on dendrobiums. 99% of fungus and bacteria is a rather bold claim. Personally I'm doubtful of the claimed efficacy of "organic" fungicides, but that's my opinion.

calypsoB · #3 06-04-2011, 01:46 AM

I have used this spray before on other things and it works like nobody's business!

Ray · #4 06-04-2011, 10:13 AM

Quote:

Originally Posted by OrchidThief79

I've been investigating fungicides a lot recently. The main fungicides used on orchids are Physan, neem, copper compounds, and a variety of chemicals such as mancozeb and thiophanate methyl. I haven't heard of using thyme, but I can't imagine that it would be harmful at all given that humans eat it. The only fungicide that can be harmful to orchids is copper, and that's only on dendrobiums. 99% of fungus and bacteria is a rather bold claim. Personally I'm doubtful of the claimed efficacy of "organic" fungicides, but that's my opinion.

There are plenty of orchids besides dendrobiums that are sensitive to copper, especially "thin-leaved" ones like coelogynes, catasetum, and the like. Don't forget that copper sulfate, the active ingredient of the product, is a herbicide at elevated concentrations.

I have not used it myself (no fungal issues in my greenhouse), but I have sold a lot of Oleotrol-M to organic growers. It uses the physical driving force of nature to lower surface energies to disrupt the cell walls of the pathogens with nanoparticles of vegetable oils. It is not a "smotherant" like neem or ultrafine oils - the applied solution is only about 0.02% oil.