Hi all!!
This is my first post at Permies forum!!
I also tried to find out the science behind companion planting an year back. I think the book "Carrots love tomatoes" is considered to be a classic in this. This article
Companion Planting Logic resonates with my reasoning! In my garden I always do companion planting, but to say that there is a definite benefit I would have to do trials a bit more scientifically. And also sometimes despite the best efforts, pests do make way.
Sai!