Plant of the Week
Devil's Tongue
Latin: Amorphophallus konjac
Those of us involved in extension work are often asked to identify plants.
Usually, it’s to satisfy nagging curiosity, but occasionally it takes on more
significance as when a child has eaten an unknown plant or the police need to
identify plant fragments found clinging to the clothes of a murder suspect.
This week's sample of interest was
of the curious variety, and it's easy
to understand why a blooming specimen of Devil's
tongue would arouse such curiosity.
Devil's tongue (Amorphophallus
knojac) is a member of the philodendron (arum) family. The calla lily flower
can be thought of as basic model for the family with a leaflike spathe
surrounding a protruding column of tiny individual flowers called the spadix.
But in nature's grand measure of
diversity, these flowers may be tiny or mammoth, which is the case with devil's
tongue. The plant, from southeast Asia, produces a large tuber which can weigh
22 pounds and be as much as a foot across.
From mature tubers, a single flower stalk arises which can reach at least 5
feet high. The showy pink spathe unwraps from this stem like an upside down
designer mini-skirt with a generous split up the side. The largest flower in the
world belongs to an Indonesian relative, the titan arum (A. titanum),
which produces a bloom as much as 12 feet tall.
From the center of the mini-skirt extends a giant burgundy to brown spathe,
which may be as much as 2 feet long and as thick as your arm. In nature, the
plants have evolved to be pollinated by flies, so, to attract the pollinators,
it mimics the scent of dead water buffalo.
The foliage of Devil's tongue is
equally unique. After flowering, a single leaf forms, which can grow as tall as
4 feet and spread out in the fashion of an umbrella frame to look like a giant
dissected mayapple leaf. The leaf petiole is often marked with patches of dark
green or brown giving rise to common names such as leopard arum or umbrella
arum.
On researching Devil's tongue, I
discovered it is one of two Amorphophallus that are cultivated for their edible
tubers. The Chinese have grown it for over 2,000 years, and today it is a
relatively important starch plant in Japan. It’s sold in blocks like tofu and is
used in soups and stew-like dishes to provide a chewy texture.
Devil's tongue is not hardy out of
doors and must be treated as a houseplant. A specialist with the International
Arum Society informed me that A. konjac is becoming quite common in the
plant trade but this is my first encounter with a blooming specimen. According
to the discussion on the web, this is the easiest and most dependable flowering
of the Amorphophallus species.
The family who owned the flowering specimen under discussion had been growing
it as a houseplant for 10 years and were unaware that it bloomed. They treated
it as a typical houseplant and grew their specimen in a 10-inch pot.
Progressively larger pots and routine fertilization during the growing season
would speed the growth of the tuber and hasten flowering. The plant can be
over-summered out of doors in the shade but must be protected from freezing in
the winter when the tuber goes dormant and dies to the ground.
By: Gerald Klingaman, retired
Extension Horticulturist
- Ornamentals
Extension News -
April 5, 2002
Back to Archives A - D
|
