Common Name: Louisiana Canna

General Information

Canna glauca is a perennial plant producing small to large clumps of stems up to 150cm tall from a far-creeping, thick, tuber-like rhizomatous rootstock[, ]. With its large leaves sheathing a central stem, the plant has the appearance somewhat like a small banana plant.
The plant is sometimes harvested from the wild for its root, from which an arrowroot-like edible starch can be extracted.

Known Hazards

None known

Botanical References

,

Range

S. America - Argentina, Uruguay, Paraguay, northwards through C. America to Mexico and Texas; through the Caribbean to Florida, S. Carolina.

Habitat

Margins of marshes, swamps, ponds, and wet ditches; at elevations up to 100 metres[].

Properties

Edibility Rating
Habit	Perennial
Height	1.50 m
Pollinators	?Hawkmoths
Cultivation Status	Wild

Cultivation Details

Canna glauca is not very hardy outside the mildest regions of the temperate zone. It succeeds outdoors in southeastern USA[] and also in southwest England[], though there there it requires a good protective mulch over the winter to protect the roots[].
Requires a deep rich well-drained soil in a sunny position[]. In its native habitat this plant is often found in wet soils and also shallow standing water[]. The plant has large leaves and dislikes windy conditions since this can tear the leaves to shreds[].
Plants are fast-growing, and can produce a flowering shoot in their first year of growth from seed[].
Plants can be grown as summer bedding in many parts of the temperate zone, the tubers can be dug up in the autumn after being lightly frosted. They can then be stored over winter in a cool but frost-free place in moist soil or leaves[].
Slugs love the young growth in spring and can cause serious damage to plants[].

Edible Uses

Root - cooked[]. The starch can be extracted and used as an arrowroot[, , ]. The arrowroot is obtained by rasping the root to a pulp, then washing and straining to get rid of the fibres[]. Very young tubers can be eaten cooked, they are sweet but fibrous.

One report suggests that the fruit may be edible but gives no further details[]. As far as I know the fruit is a dry capsule[].

Medicinal

None known

Other Uses

None known

Propagation

Seed - the different species in this genus often hybridize and so seed cannot be relied upon to breed true. If growing from seed, pre-soak for 24 hours in warm water and sow in the seeds in late winter/early spring, 2 - 5cm deep in individual pots in light shade in a greenhouse at 20°c[, ]. Scarifying the seed by carefully removing a small part of the outer shell (being careful not to harm the seed itself), to enable it to imbibe water can speed germination, especially if the seed has not swollen after being soaked[, ]. The seed usually germinates in 3 - 9 weeks[]. Grow the plants on in a greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.
Division of the root clump as the plant comes into growth in the spring. Each portion must have at least one growing point. Pot up the divisions and grow them on in the greenhouse until they are well established and then plant them out in the summer.
Root cuttings.