Fusarium killed all my orchids

Are you certain you were dealing with fusarium? It's actually relatively rare, and is not known to spread that readily unless poor hygiene is practised.

What were the symptoms?

You cannot stop vendors from selling, but you can stop doing business with them.

 

Sometimes it is cheaper to invest in an old good systemic fungicide, than start from scratch several times

 

Or a probiotic.

 

I have had problems with fusarium but only on two plants on a collection of hundreds. For fusarium to be killing all your plants two things need to happen, first your plants need all to be highly susceptible to this fungus, the conditions for the growth of fusarium must be near optimal. I would advice checking on your growth area to see what things you can do to make it unfavorable for fusarium growth. Also most general are never bothered by fusarium, I have yet to see a Dendrobium showing the corky areas near the base of the canes that are a trait of fusarium infection. Also you might want to check on which orchids you are trying to grow and to try plants that are not susceptible to this fungus. Personally, I try to avoid any orchid that needs constant application of pesticides/fungicides to survive in my garden.

 

I'll bet "justagirl" is yet another victim of Miss Orchid Girl's video. After its release, suddenly a bunch of people suddenly saw fusarium infections...

 

I have seen some "advice" videos on Youtube that had made me shudder with horror.

 

The web is ideal for spreading nonsense and some people use it extensivley.

Desinformation to it‘s best.