Elephant Foot Yam, Giant Forest Yam /Amorphophallus Paeoniifolius/
Elephant Yam is a tropical forest dwelling perennial plant cultivated for its edible tuber in lowland tropical countries in Asia, Africa and the Pacific Islands. It is a traditional food of Indigenous Australians in Cape York and Northern Territory.
It produces a single patterned stalk up to 2m annually with a large single leaf. The plant produces only one short flowering stem annually. When ripe for pollination, the flowers have a foetid smell to attract carrion flies and midges. This smell disappears once the flowers have been pollinated.
It produces a massive underground tuber that can weigh up to 25 kilos.
Can be boiled, baked or fried just like potatoes.
It is used in curry, pickles and chutney.
Used to make a starch used in Japanese cooking to make a tofu-like curd.
Konjak noodles are made from the carbohydrate-free starch.
Loose leafy detritus in moist shady habitats
It dies back in Winter and reshoots in early Summer.
When the plant is mature, it will produce a flower in Spring, which sprouts directly from the soil.
It requires moist humid and warm weather during the vegetative phase and cool and dry weather during the corm development period.
Elephant Yam prefers to grow in dappled shade, as an understory so is perfect for growing in a poly-culture or food forest.
It prefers a moist but well-drained, humus-rich, fertile soil.
The plants are usually grown on a three-year cycle.
An interesting technique used in Indonesia is to dig up the tuber after one year and then replant it upside down. This stimulates the lateral buds into growth and increases the overall size of the tuber.
They can also be grown in a pit of about 1m square filled with aged manure and compost prior to planting. This produces large corms that are easy to harvest.
Corm – cooked, must be thoroughly boiled or baked.
Young leaves and petioles – cooked and used as a vegetable.
The tuber is cut into 750g small pieces in such a way that each piece has at least a small portion of the ring around each bud.
An ordinary sized yam gives about 6 to 8 pieces for planting.
The cut pieces are dipped in ash to prevent rotting from the cut surface.
Whole corms of 500g sizes can also be used as a planting material.
The cut pieces are planted in beds at 50 cm spacing. The pieces are planted in such a way that the sprouting region (the ring) is kept above the soil. Sprouting takes place in about a month.
Risks and weed potential
Some cultivated varieties contain calcium oxalate crystals, which if eaten fresh, makes the mouth, tongue and throat feel as if hundreds of small needles are digging in to them. However, calcium oxalate is easily broken down either by thorough cooking or by dehydrating, rendering it safe to eat.
Harvesting & Processing
Corms are usually harvested when three years old, at this stage they can weigh up to 9kg.
When the stem and leaf die back the tuber is ready to harvest.
Corms can also be harvested annually when the stem and leaf die back.