A basic setup involves a wooden pole, a copper spiral winding upward, and a grounding spike or buried wire

https://devinillo253.tearosediner.net/electroculture-and-compost-tea-synergies-for-plant-vitality

A basic setup involves a wooden pole, a copper spiral winding upward, and a grounding spike or buried wire, positioned near crops to capture atmospheric ions and gently influence local electrostatic conditions.