I tried it last year for a while the plants were doing really well. I did not use a spiral antenna I used a Yagi antenna type which learnt about from a guy on Youtube.

Asked Matt Powers about it and he said it was interesting but he did have concerns about potential copper toxicity. It's also not the easiest element to remove from soil. Packed it in because I don't have much space here and I am giving things plenty of Biochar anyway. I will give another go in the future perhaps when I can monitor these things better.

I think it would be great if you plant some with the antenna going the wrong way. Personally I don't think it will make any difference. I am sure it's doing something with the EH in the soil which is a very interesting subject in itself.

So as you are eating these as your main crop do watch out for signs of copper toxicity in yourself.

You can learn a bit about EH in the podcast below, Olivier Husson also has a free course on it which is worth doing :

https://regenerativeagriculturepodcast.com/episodes/redox-the-driver-of-soil-microbial-interactions-and-nutrient-availability-with-olivier-husson-2/