Amorphophallus konjac

Devil’s Tongue • Konnyaku

I bought a single corm of Amorphophallus konjac from Fraser Thimble Farms, Saltspring Island, BC in 2006. I chose the species by the written description in  the catalogue: it sounded unusual and large, and I was interested in other plants in the Arum family, such as Skunk Cabbage, Calla Lily and Cobra Lily. The corm produced a small stalk and umbrella-like foliage in the first spring, the foliage dying back after a few months. I  cut off the stalk and left the corm, still in its pot, to overwinter in the cool dark basement. In March of the next year, the plant was brought into the light  and watered and in  April, a new shoot emerged. Over the next 4 years, the plant flourished, producing an ever larger stalk, and foliage that reached 1 m across. Each winter the corm rested in the basement. In February 2011, I noticed  that a 5 cm shoot had emerged above the soil surface. The shoot was  twice as tall in  a week, and it continued to grow at a rate much greater than other years. As well, the apex was red with a structure that was definitely not leaf-like.  After 5 years of nurturing, the Amorphophallus was producing an inflorescence.

I knew that it would produce an odour to  attract its fly pollinators, but was overwhelmed by  the smell when the flowers opened. For 2 days, it smelled like a dead animal. The spadix collapsed about three weeks after flowering. I expected that the corm would die,  but after several days, an emerging stalk began its growth, attaining a height of  80 cm, with foliage 120 cm across.

In Amorphophallus, as well as other plants in the Arum family, the large, flower-like structure is actually a modified leaf called a spathe. In its centre, a long column – the spadix – produces tiny male and female flowers along its surface.  The corm is an underground stem that stores nutrients and the foliage is a single trifoliate leaf on a long petiole.