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

https://www.scribd.com/document/1032037849/ElectroCulture-vs-Traditional-Gardening-Pros-Cons-and-Outcomes-185382

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.