my wife loves orchids and has acquired quite a few which adorn
our porch - sitting on the wall in pots or suspended from the ceiling.
However ants keep attacking and eating the blossoms.

She has resorted to putting pots in larger pots filled with water,
but they keep on attacking.

Is there some "pesticide" that keeps the ants away without harming the orchids?
MB - not a garden or flower buff