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

https://medium.com/@mirienkioi/electroculture-gardening-my-first-90-days-of-results-e313b42f53c9

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.