Posted by Phytopath on Mar 11, 2010
Canna edulis , known in Australia as Arrowroot and elsewhere as Achira.
The plant can be described as a soft wooded perennial or an herbaceous perennial, depending where it is grown. Growth is approximately 2.5 metres (around 8ft) high and the width depends on the spread of the underground rhizomes. The soft fleshy leaves arise from the somewhat soft, easily bent stems.
The general appearance of the plant is that of the ornamental canna (Canna indica), to which it is related. The flowers of arrowroot are red to orange/gold and smaller than those of the decorative variety.
The plant is thought to have originated in the Andean region because of archaeological remains from Peru. Commercially, plants are grown in Queensland Australia, Hawaii, Central and South America and the Pacific Islands.
I have found Arrowroot to be exceptionally hardy in the garden and easy to grow in my climate. They will grow in most soil types as long as the drainage is good. Poor drainage will lead to rotting of the rhizomes. Most gardening books advise that the plants need full sun for growth and will not tolerate shade but in my garden they are happily growing in the shade of mature Eucalyptus trees (see photo).
During the growing season make sure the plants have adequate moisture (don’t you love that term, ‘adequate’, what does it actually mean?). For me, I make sure the plants don’t get to the wilting stage. During winter, I do not water the plants at all.
Give them a sheltered spot otherwise the leaves can be shredded by strong winds which looks unsightly but has no affect on the goodness of the root. (It’s an aesthetic thing).
The leaves, root and seed are edible. The young shoots are cooked and eaten as a green vegetable and the immature seed are used in tortillas.
The root is used raw or cooked and is the source of Arrowroot. It is rasped to a pulp then washed and strained to get rid of the fibres. The starch easily separates from the fibre of the root and is easily digested.
In Peru the roots are baked for several hours until they become a translucent white colour and slimy or mucilaginous (sounds divine…) and sweet. In Vietnam Arrowroot is grown commercially to produce transparent noodles.
The dried root is high in starch, containing as much as 80%. It also contains 10% sugar and 1% to 3% protein.
I have grown up with ‘Milk Arrowroot’ biscuits available from the supermarket, so I am loath to dig up my beautiful Arrowroot plants that are growing in the garden. Besides, it sounds like too much mucking about to get the actual starch, before you even think about baking biscuits.