Ant farmers

[Digeroo]

I am really struggling with ants farming aphids on my runner beans.  Almost every leaf has a dark patch on the underside with an attendant ant.  And they then seem to be moving to the flower heads.
I have been using a small sprayer to wash them off.  But they are coming back quicker than I can remove them.
Any suggestion for getting rid of them please.
I have stinging nettle tea brewing, but getting it onto the underside of the leaves is difficult.   

[Digeroo]

[Obelixx]

Find the ants' nest and put down some poison or fill it with water so they move on?

[Digeroo]

I have tried to find the nest but think they might be coming quite a way.

[Obelixx]

Then maybe some poison at the base of the affected plants.  The stuff in those tins shaped like old fashioned shoe polish seems safe to use as it won't be taken by other critters.

[rowbow]

Debris powder, used for the chicken red mite, puff around the ant nest.