Back in the 70’s when I was first getting interested in gardening I read a book “Findhorn Garden” (1976, at Amazon.com used for $3). It was an extraordinary tale of ten people living for three or four years in a very remote and barren part of Scotland; mostly rocks and sand.
They started a vegetable garden and (stay with me here) they were able to communicate with the garden plants through spirits they called devas. Being able to learn what each plant needed, they grew incredibly large and very tasty vegetables every year; plants so large no scientist who visited them could explain the phenomenon. After thirty years I am not ready to disbelieve the Findhorn Garden story as weird and implausible as it sounds.
Because in the last 25 years scientists have confirmed that plants of the same species are able to communicate with each other. In one research project the researchers were able to take note when the first gypsy moth larvae landed on a mature oak tree in a grove of other oaks. By analyzing the chemistry of the first oak tree’s leaves they were able to determine that within a very short period of time the tree had added a bitter tannin to all of its leaves making it an unattractive lunch for the gypsy moth larvae. What was astounding was that all the other oak trees in the grove changed the chemistry of their leaves making all of the trees unappetizing to the attacking pest.
It took a few years for the scientists to determine just how had the trees in the rest of grove get the word that the gypsy moth larvae were in town. Those trees did not communicate through their roots. They released a special gas or pheromone to warn their neighbors of the danger. Since then there have been studies to confirm similar behavior among walnut trees and willow trees. The assumption is that all species of trees can communicate with each other in this fashion.
Another shocker - trees have been found to communicate not only for defense, but also to time their blooming. In fact, blooming at the same time can also be a defense mechanism, as the destructive pest insects will not have enough time to eat too many flowers, as it would happen if trees bloomed one after another.
It gets better – Some varieties of corn defend themselves against the root worm by emitting a pheromone that attracts microscopic beneficial nematode worms that kill the root worms.
Finally, it has been proven that plants that are in stress of any kind release some kind of gas and that gas is how the pest insects find the weakest plants.
I assume we have just touched the surface of all the biological magic that occurs in and among plants in our home landscape. Read the Findhorn Garden; it’s a perfect read for a snowy winter day.