It might control a bit but never supress completely.
The goal with biological control is to "work with nature", and yes, that often means only controling some pests and not trying to eradicate them (they often will be back anyway with many new plants coming from orchids producers using chemicals... I received bugs from
almost every growers.)
I did not see any mealies in my collection for more than a year now. I am pretty sure there are still a few in my 500 plants but at such a low level that they are not disturbing. And, gosh, I saw a few thrips last months.... One plant showed Erwina last week... Only one and the plant will survive for sure!
And for many plants flowers last for months, not only a few days.... And many people got some of my plants and they never complained about pests... I just don't have real problems with disease now. Actually, my plants are healthier than ever.
By the way... I used "strong" chemicals for
decades!!!! For my personnal use, but also at work. I applied many stuffs or have been in close contact with many "strong chemicals" : Cygon, Orthene, DDT (yes... DDT ), Chlordane, Benlate, 2-4-D, nicotine bomb (I add such nicotine in my blood my insurance company though I was a smoker...), etc.
Then one day, I decided enough is enough. It was not easy though since all is a matter of balance with biological control. I had to think differently. I now see myself like an "ecosystem manager"
What I mean is....if something doesn't work for someone, it can work for other people.
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