For balcony growers, compact coil pots use a small copper helix inserted into the medium

https://thrivegarden.com/pages/your-guide-to-initial-costs-and-investment-in-electroculture-gardening

For balcony growers, compact coil pots use a small copper helix inserted into the medium, aiming to localize subtle charges near roots without requiring tall poles or complex grounding arrangements.