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

https://lanedhan819.tearosediner.net/electroculture-and-mycorrhizae-friends-or-foes

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.