Manihot grahamii or Hardy Tapioca is the only hardy Cassava. It has beautifully incised leaves.
The plant dies back when it freezes but growth resumes next spring and the plant grows up to about 2 m high each year. It can also be grown as a container plant.
The plant is invasive. Originally from South America but now naturalized in North America and Australia and specimens have also been reported in Europe (Italy).
Leaves and other plant parts contain a toxic latex.
Manihot grahamii is a shrub or tree which grows up to 3.5 m. It forms an umbrella-like dense foliage group at the top. The trunk is up to 10 cm in diameter, the bark is smooth and reddish brown.
The leaves are alternate, on a petiole of up to 15 cm long. They are palmate, with 7-9 lobes, up to 10 cm long.
The inflorescence is a monoecious raceme of 15 cm long. The flowers are bell-shaped, with 5 petals, yellow-green. The flowers attract bees.
The fruit is a three-carpellate dehiscent capsule of 1.5 cm long. The seeds are gray, brown or mottled and elongated in shape, 1.2 cm long.
Graham’s cassava, hardy tapioca, wild cassava
Janipha loeflingii var. multifida, Manihot dulcis var. multifida, Manihot enneaphylla, Manihot lobata, Manihot loeflingii var. multifida, Manihot palmata var. multifida, Manihot tweedieana fo. nana, Manihot tweedieana, Manihot tweedieana var. lobata
Manihot: from the Guaraní name (Paraguay language)
Grahamii: after Robert C. Graham (1786-1845), Scottish physician and botanist
USDA zone 7-11
Slightly acidic to neutral soil, rich in humus
Sun, partial shade
Grows best in a moist place but resists drought
Every two weeks during the growing season
Seed, division of the root ball, cuttings
- sow in spring spot or indoors
- room temperature