Metal planter paint treatment

[Rash55]

Hi everyone, need some advice/help on what paints/sprays could stop the colour running from metal planter frame.

The bottom part of the metal planter frame looks corroded and whenever it rains or when the neighbour waters the plants the white watery substance leaks onto my window below leaves the below stains.

Is there some type of special paint/spray that could stop this from happening?

 

[foxhole]

No, needs a sheet of plastic etc fixed below to deflect water away from wall .

 

[Rash55]

Any other suggestions?

Thanks