Systemic fungicide

[Cody]

What's everyone's preferred systemics available in the US?

 

[Ray]

Any copper-based product will be a systemic fungicide and bactericide.

 

[treefrog]

Yes, slipper orchids react well to these copper-based fungicides. Here we easily find a product called 'Bouillis Bordelaise' consisting of copper sulfate + calcium oxide.

However, a small warning, I have found that some plants can be badly damaged by this fungicide. The first are bromeliads that will loose any leaves in contact with the solution. I also saw important damages in Gongora orchids and Utricularias. Most other orchids I have Cattleya, dendrobium, Oncidium, etc. do very well with the Bouillis Bordelaise.

Here is an Alcantarea bromeliads treated with copper-based. I successfully treated the tiny fungus spot at the end of the top leave . Congratulations Mathieu!

Cheers,
Math

 

[mrhappyrotter]

However, a small warning, I have found that some plants can be badly damaged by this fungicide. The first are bromeliads that will loose any leaves in contact with the solution

Copper toxicity is a known issue with bromeliads. It's one reason I am super careful when applying it, because I have a lot of broms interspersed with the orchids. Also, I was under the impression that copper based fungicides are (or can be) toxic to certain types of Dendrobiums, so I avoid spraying on that genus.

However, I am under the impression that most of the copper and sulfur based fungicides are not systemic.

As for systemic fungicides, I can't say I have a preferred one. The ones I've looked into all seem to have a balance of pros and cons. More recently I've been testing out the use of "-strobin" (ex: azoxystrobin) based fungicides on a preventative basis due to their effectiveness and supposedly there's some added benefits for some types of plants (improved growth or added tolerance to high temps). The major downsides are the cost and the fact that you have to use them in combination with other fungicides and/or ensure you rotate with other fungicides that have a different mode of action due to concerns of developing resistant strains of fungi.

I'll be interested to see what others are using and recommend. Fortunately, and I'm knocking on wood here, I don't have much verifiable fungal infection in my orchids, so it's not a big concern for me. Roses on the other hand, those things might as well be called fungus food in my hot and humid climate.

 

[Ray]

“Bouillie Bordelaise” translates to what we call “Bordeaux mix”. It used to be used more prevalently here than it currently is.

Yes, copper is systemic.