A basic setup involves a wooden pole, a copper spiral winding upward, and a grounding spike or buried wire
https://jaspercymx504.cavandoragh.org/electroculture-gardening-on-a-budget-low-cost-tools-and-tips-2
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.