That was my introduction to Amorphophallus konjac, one of the few of the genus known to be hardy in much of the US. It's rated from USDA zones 6 - 10, but I have read posts from people, on the Aroid-L email list, growing it in the ground in USDA zone 4, Michigan. A post from Florida (USDA zone 10b) stated that it does not do very well in south Florida, probably due to the summer heat. A. konjac is, perhaps, the most common representative of the genus in cultivation. It is still often found under the old, incorrect name of A. rivieri or A. rivieri 'Konjac'. The common name is devil's tongue.
Knowing nothing about this plant and fearful of its hardiness, I planted the tuber at the base of an east-facing slope in a wire basket to ward off rodents. I later found that rodents won't eat them because of the oxalic acid crystals in the tubers and I was warned that the basket might constrict the tuber, which can get quite large (some boast of tubers that are head-sized). With that information, I dug mine up and removed the basket! The original tuber has since formed offsets so that I now have a nice colony of six or eight stems.
The striking foliage on my plants emerges very late; sometimes not until late June - always making me think they have disappeared. Like all of this genus, each tuber produces one stem (petiole). Mine get about two to two and half feet tall (.6 -.76 m), but they can exceed three feet (.91m) in height. My plants are easily over two feet wide (70 cm). I have read that the larger the tuber gets, the larger the leaf gets!
Typically, each tuber produces one petiole, although immature specimens of some species will produce two stems at a time. At the top of the stem, the complex, umbrella-like leaf blade (lamina) divides, giving the impression of many leaves. In some species this can be tree-like.
Most of the species, whose foliage I've seen in photographs or in person, are somewhat similar, although some form a horse-shoe shape rather than typically branching. But, Amorphophallus linearis has very slender, linear sections that are almost grass-like in shape. A. konjac's foliage remains pristine all season until frost knocks it back; I've never seen it bothered by any insect; my deer herd never touched it and, growing in a shady spot, it does not get burned.
