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

https://medium.com/@holtongqtl/the-electroculture-advantage-why-plants-respond-to-electricity-5f2fd31176f3

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.