It is Winter in the Northern Hemisphere and the Lithops are in their resting period. I thought I’d take the opportunity presented by this quiet moment to discuss some of the more technical points of the genus and maybe help some “fence sitters” discover how fascinating these little plants truly are!
The word ‘Lithops’ is derived from Greek ‘lithos’ meaning stone and ‘opsis’ meaning appearance. An apt name for this particular genus of the family Mesembryanthemacea, Lithops morphology allows them to blend seamlessly into the rocky habitat in which they are found in nature and has brandished them with their affectionate name “living stones”. They are a diverse group, with species and subspecies and varieties, and this diversity is beautifully displayed phenotypically in their tiny plant bodies. I think this is the best quality of Lithops; the diversity and variation within not only the genus, but species and subspecies as well. A bowl full of Lithops is a treat to behold as one marvels over the uniqueness of each plant and ingenuity of their design.
Not just another pretty face, the Lithops is a master of survival and adaption. A true minimalist, it is essentially nothing more than two leaves fused together. Its only extravagance lies in the patterns and colors it displays on its face. While inarguably beautiful, the islands, peninsulas, and windows that characterize the genus into various taxonomical classification systems are also functional, creating a complex system to catch sunlight for photosynthesis without compromising their camouflage. While other plants reach for the sun, invariably becoming fodder for grazing animals, the Lithops is able to enjoy relative anonymity among the pebbles and stones.
So how does it work, this complex system derived to harvest the sun’s energy? Quite ingeniously, actually! As the light enters the plant through the translucent windows, it is deflected by the islands and peninsulas. It is then dispersed by the water storage tissue inside the leaves such that it is pickup by the chlorophyll rich sidewalls. At this point it becomes available to the plant for the synthesis of foods from carbon dioxide and water. I imagine this process to be reminiscent of the inner workings of a pinball machine – sunlight being the ball, the islands and peninsulas being the flippers, the water storage tissue being the various bumpers and slingshots, and the chlorophyll holding sidewalls being the targets. Brilliant, isn’t it? So when people ask, “Why Lithops…don’t you think they are kind of boring?” my response is, “Are you kidding me?”.