Do Marijuana Plants Have Feelings?
If plants have feelings, one day, in a world of marijuana legalization we might hear Beethoven playing across Mexican fields of pot.
I remain keenly skeptical about claims that people have communed with geraniums, passionflowers, and Dracaena Massangeana let alone weed. Even that fascinating book The Secret Life of Plants by Peter Tompkins and Christopher Bird has failed to persuade me that vegetables are sensitive to threats, affectionate words, or recordings of Beethoven’s Ninth Symphony. Though I am persuaded that certain cannabis responds to Bob Marley and Coldplay. Without appropriate receptors for receiving and processing sound, it is hard to believe that plants are capable of such feats. But there are two avenues of respectable research that should trouble anyone adopting this orthodox stance.
Mulling through the learned journals I came across examples from each—reports showing that plants do indeed have sensory abilities well beyond our present scope of understanding. More and more evidence is emerging that conflicts with the commonly held view that forest trees, garden shrubs, and humble mosses are unsophisticated life forms dependent only on a passive supply of sunshine, water, carbon dioxide, and simple nutrients from the soil. There’s more, possibly much more, to plant behavior than we suppose. One day, in a world of marijuana legalization we might hear Beethoven playing across Mexican fields of pot.
Moon's Gravitational Pull
First, consider the strange results presented in the International Journal of Biometeorology by Dr. E. Graviou, who works at the University of Lyon in France. Using highly sensitive equipment, Dr. Graviou was able to monitor the only measurable activity of seeds kept in total darkness at a constant temperature—the minute amount of oxygen uptake necessary for their survival. The results were astonishing. For example, with one species of tomato, Dr. Graviou found not only that oxygen consumption levels in the morning and in the afternoon “oscillated” (one being high when the other was low) but, even more surprising, that uptake of oxygen was significantly greater on mornings occurring at 15-day intervals coinciding with the new and full moon. Sunflower seeds behaved in a similar way.
Although the explanation underlying this strange phenomenon is still not fully understood, there seems little doubt that the lunar cycle influences the life processes of plants. Perhaps gravity is the crucial link, though atmospheric pressure is also known to vary with the moon’s phases. In theory, the moon’s pull on water underground can have a direct impact on your marijuana. The period between a new moon and the final full moon is referred to as the waxing phase. The moon continues to get bigger during the cycle and so should your plants. Whatever the mysterious forces may be, we now have to accept that heat, light, and nutrients are by no means the only factors regulating plant behavior.
Color Perception in Plants
The second paper that caught my eye was titled “Color Perception in Plants”— surely a bizarre concept to feature in the sober pages of Trends in Biochemical Sciences. Here is a cautious British academic, Professor Harry Smith of Nottingham University, discussing not just how plants respond to light waves but how they experience color. To appreciate this novel notion, we must re¬call how leaves react at all to light. Two substances are involved. One is sensitive at the blue end of the light spectrum, and though it occurs in both primitive and higher plants, we know little about how it works. The other, phytochrome, seems to be the sensor molecule that gives leaves the capacity to discriminate colors.
What happens is this. Phytochrome exists in two different forms that can be converted from one to the other depending upon the wavelength of light that strikes the leaves. The first absorbs red light most efficiently, the second maximally absorbs longer wavelengths at the Infrared end of the spectrum. Since the relative proportions of the two forms of phytochrome are determined by the wavelengths of the light falling on the plant, leaves containing these substances can “monitor” the color of light surrounding them. Just as pigments in our retina tell us that the sky is blue and a matador's cloak is scarlet, so phytochromes give plants similar information. Professor Smith and his colleague Dr. M.G. Holmes have found that this unexpected vegetable talent serves practical purposes too.
In nature, the commonest reason why plants are sometimes deprived of light is that they become shielded by other species. The deprived plant suffers particularly from a shortage of red light because chlorophyll, the substance that green plants use to transduce the radiant energy of the sun into chemical energy for manufacturing food, absorbs light predominantly from the red region of the spectrum. But infrared light still reaches the shaded plant, causing an alteration in the relative amounts of the two types of phytochrome so that the plant can absorb more light of infrared wavelengths. This in turn provokes the shielded plant to proliferate and thus overgrow its competitors.
The ability of plants to perceive the quality of the light is of greater importance to certain species than to others. In some ecological niches, such as woodland, flowers do not respond particularly vigorously to variations in the phytochrome mixture. In herbaceous habitats, though, weeds use their color sensitivity to great advantage, astounding gardeners with their potential for smothering carefully cherished species. As with Dr. Graviou’s discovery, much more research is needed to illuminate the more exotic sensory abilities of plants, which until recently were barely known to exist. Whether or not plants are really capable of understanding what we say and think about them is still open to debate. But one thing is for certain, they are by no means the “vegetables” we once thought them to be.