My mother in law always did this, I though it was the chemicals in the peel that made it work so well. Just flatten a banana peel and bury it under one inch of soil at the base of a rosebush. The peel’s potassium feeds the plant and helps it resist disease...works for tomato plants too.
Plants have best friends just like people do. Marigolds help tomatoes and roses grow better. Nasturtiums keep bugs away from squash and broccoli. Petunias protect beans from beetles and oregano chases them away from cucumbers. Geraniums keep Japanese beetles away from roses and corn. Chives make carrots sweeter, and basilmakes tomatoes even tastier.
The Backyard Garden: Plants that help other plants grow