by Wilbert Hetterscheid
The information here in is adapted from W. Hetterscheid and S. Ittenbach, 1996, Everything You Always Wanted to Know About Amorphophallus, but Were Afraid to Stick Your Nose Into!!!!!, Aroideana 19: 7-131.
Amorphophallus paeoniifolius (Dennst.) Nicolson [Synonyms: A. campanulatus Decne (non Roxb.), A. dubius Bl., A. sativus Bl., A. decurrens (Blanco) Kunth, A. chatty Andre, A. virosus N.E.Br., A. rex Prain, A. malaccensis Ridl., A. gigantiflorus Hayata, A. microappendiculatus Engl., A. bangkokensis Gagnep., A. dixenii Lars. & Lars.].
Description: Tuber depressed-globose, to about 30 cm in diameter, about 20 cm high, dark brown, root scars prominent, annulate, offsets produced every season, these thick rhizomatous, to about 10 cm long, about 4 cm in diameter. Leaf solitary or two; petiole to about 2 meters long and about 20 cm in diameter, background color pale to dark green or blackish green, usually with large and small pale blotches and numerous tiny dark dots, the large blotches often confluent, especially near the base, surface shallowly corrugate to strongly echinate-verrucate; lamina highly dissected, to about 3 meters in diameter; leaflets rounded, oval, ovate, obovate, elliptic, elliptic-oblong, elliptic-lanceolate or lanceolate, acuminate, 3 to 35 cm long, 2 to 12 cm in diameter, upper surface midgreen, lower surface mid-green or pale green. Inflorescence short-peduncled; peduncle 3 to 20 cm long, about 1 to 8 cm in diameter, usually paler and smoother than petiole; spathe campanulate, broader than long, 10 to about 40 cm long, 15 to about 60 cm in diameter, base and limb often separated by a shallow constriction, limb spreading, strongly undulate, base outside very variable, background color ranging from pale green to dark brown, usually with large and small, circular paler spots, base inside lower part deep maroon, upper zone dirty whitish or very pale pinkish, limb outside as base but with more prominent maroon flushes, especially near the margin, limb inside usually glossy dark maroon, base within densely verrucate, verrucae variable, mostly conical, fleshy. Spadix sessile, shorter or longer than spathe, 7 to about 70 cm long.
Distribution: Madagascar, eastwards via India to Malesia, southern China, Indochina, Polynesia, northern Australia (in almost all imaginable secondary conditions, either secondary forest or highly disturbed areas, in dappled shade or fully exposed areas, altitude 0 to 700 meters).
Notes: The large number of synonyms presented here originates from many an author's attempt to define a set of the variable characters of A. paeoniifolius as supporting the separation of new species from the main body of the species. The main body being specimens with large, pyramidal appendices, very long styles, bilobed stigmas and fairly rough petioles. Mostly the spadix is longer than the spathe but in inflorescences developing from small tubers this is reversed, and occasionally the appendix takes a more isodiametric shape, but this may also be found in large specimens. The relative length of the female zone compared to the male zone varies at random. The shape of the male zone depends strongly on the width of the appendix base. When the latter is large, the male zone is often roofed against the underside of the appendix resulting in a strong obconic shape. Alternatively, when the appendix base is narrow, the male zone is cylindric or only slightly obconic. The degree of roughness of the petiole may vary within one clone or specimen but is usually constant. In certain areas roughness is ubiquitous (e.g. in Papua New Guinea), but may vary from rough to near smooth (e.g. Java, India). So far no correlation between any of these characters has been found on a large scale. Amorphophallus paeoniifolius has a centuries old cultivation history in the Asian and Indopacific region and its natural distribution has been totally obscured because many specimens found in the wild are (probably) weedy escapees from cultivation. The closest relative of A. paeoniifolius is A. hirsutus.
Cultivation: Grow in any fertile soil. The tuber may be stored dry when dormant.