In one of my favorite flicks, Tim Burton’s Mars Attacks!, Jack Nicholson as POTUS makes a final appeal to the Martians who have invaded Earth, pleading, “Little people . . . why can’t we all just . . . get along?” His answer comes after he shakes hands with the take-me-to-your-leader commander of the attack, whose hand detaches and proceeds to stab the president in the back, a Martian flag popping up from his corpse.

Let’s admit it. It’s pretty obvious from the evening news that we humans don’t get along very well with one another, and in this dog-eat-dog world, things aren’t much better for man nor beast.

But plants. Those trillium, trout lilies and anemones bursting into bloom all around us, they certainly know how to get along.

Or do they?

Unless you’ve been hiding under a garden rock, one of the hottest horticultural topics in recent years has been plant communication. In an article entitled, “Plants Can Talk. Yes, Really,” Mamta Rawat, a program director at the National Science Foundation, muses, “I think we’re seeing that the complexity [of communication] is just as great with plants as it is with animals.”

And it ain’t all friendly.

Researchers have discovered that leaves can trigger defenses when they detect predators. When some roots sense problems with nutrients, water and predators, they respond accordingly. Plants even signal nearby kin telling them that the ever-dreaded aphids (or Martians) have landed.

In fact, gardeners have had a solution for this problem for centuries. It’s called companion planting. Basil disorients moths that lay tomato hornworm eggs. Aphids can’t stand garlic! Nasturtiums lure caterpillars away from your kale, cabbage and broccoli. You can read all about these and other suggested pairings at www.almanac.com/companionplanting-guide-vegetables.

Relying on the latest scientific info instead of old wives’ tales, Benedict Vanheems, longtime contributor to Kitchen Garden, Britain’s longest-running garden magazine, digs into which plants love one another and which ones wage war on the competition. Asparagus thrives with petunias and tomatoes close by. And, yes, it makes sense to plant squash so it shades the roots of corn and to plant pole beans to climb up corn stalks. Cabbage loves garlic, nasturtiums and sage as neighbors. Peas pair well with lettuce, radish and spinach. And both zucchini and summer squash love oregano, nasturtiums and zinnias. Chemicals similar to humans’ pheromones are at work in many of these cases.

But what plants don’t play well with others? Sunflowers, walnut trees and fennel are among the plants that are allopathic, meaning they release a toxic chemical from their roots to hamper the growth of certain surrounding plants. Broccoli and cauliflower are happiest at some remove from peppers and tomatoes. And onions and garlic can retard the growth of peas and beans.

Recently, researchers found that some plants even communicate through sounds that can be picked up by other plants and animals. Although I have not heard any of my plants trash talking, plant cells can emit vibrations that other plants sense, letting them know they’re getting a little too close for comfort. Chinese researchers even observed that when they broadcast sound waves of a certain frequency in a field, crop yields improved.

So maybe you ought to talk to your plant companions, but just be sure you use a soft voice and the right frequency.