Canna
Canna indica
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Canna indica, commonly known as Indian Shot, is a striking tropical and subtropical perennial flowering plant belonging to the family Cannaceae. It is one of the most widely cultivated ornamental plants in the world, prized for its bold, banana-like foliage and vividly colored flowers that range from scarlet and orange to yellow and pink. Despite its common name 'Indian Shot,' the plant is not native to India — its range spans the tropical Americas. The dense, hard, round seeds earned it the name 'Indian Shot' because their resemblance to lead musket balls led to their actual use as a substitute ammunition during the 19th century.
Taxonomy
Kingdom
Plantae
Phylum
Tracheophyta
Class
Liliopsida
Order
Zingiberales
Family
Cannaceae
Genus
Canna
Species
Canna indica
Canna indica is native to the tropical and subtropical regions of the Americas, from the southern United States through Central America, the Caribbean, and into South America. It has been cultivated for thousands of years and has naturalized in tropical and subtropical regions worldwide, including parts of Africa, Southeast Asia, and the Pacific Islands. The genus Canna comprises approximately 10 to 20 species, depending on taxonomic treatment. Archaeological and ethnobotanical evidence indicates that indigenous peoples in the Americas cultivated Canna indica for its edible rhizomes (starchy tubers) long before European contact. During the colonial era, it was introduced to Europe as an ornamental plant in the 16th century and subsequently spread globally. In many regions, particularly in parts of the Pacific Islands and Southeast Asia, it has become naturalized and is sometimes considered invasive.
Canna indica is a robust, herbaceous perennial typically growing 0.5 to 2.5 meters tall, depending on cultivar and growing conditions.
Rhizome & Stems:
• Rhizomes are thick, fleshy, tuberous, and branching — serving as the primary storage and overwintering organ
• Rhizome diameter can reach 3–6 cm; interior is white to pale yellow and rich in starch
• Stems are erect, sturdy, and pseudostem-like, formed by the overlapping basal sheaths of the leaves
• Stems are typically green, sometimes flushed with purple or red-purple
Leaves:
• Large, broadly elliptic to oblong-lanceolate, arranged spirally in a distichous (two-ranked) pattern
• Leaf blades measure 30–60 cm long and 10–25 cm wide
• Prominent midrib with parallel pinnate venation characteristic of monocots
• Leaf color varies by cultivar — from bright green to dark green, bronze, or variegated
• Leaf margins are entire (smooth)
Flowers:
• Borne in terminal racemose or paniculate inflorescences
• Individual flowers are asymmetric (zygomorphic), 5–12 cm across
• Typically consist of 3 small, inconspicuous sepals and 3 larger, showy petals
• Petaloid staminodes (sterile stamens modified into petal-like structures) are the most visually prominent part of the flower — vividly colored in red, orange, yellow, or combinations
• Fertile stamens are reduced; the style is petaloid and flattened
• Flowers are primarily pollinated by large bees, hummingbirds, and bats depending on region
Fruit & Seeds:
• Fruit is a warty, ellipsoid capsule, 2–3 cm long, dehiscent (splits open when mature)
• Contains numerous hard, spherical, black seeds approximately 5–7 mm in diameter
• Seeds are among the hardest in the plant kingdom — they can survive passage through the digestive tracts of animals and remain viable for extremely long periods
• Seed coat is exceptionally dense and impermeable, requiring scarification (mechanical or acid treatment) for reliable germination
Rhizome & Stems:
• Rhizomes are thick, fleshy, tuberous, and branching — serving as the primary storage and overwintering organ
• Rhizome diameter can reach 3–6 cm; interior is white to pale yellow and rich in starch
• Stems are erect, sturdy, and pseudostem-like, formed by the overlapping basal sheaths of the leaves
• Stems are typically green, sometimes flushed with purple or red-purple
Leaves:
• Large, broadly elliptic to oblong-lanceolate, arranged spirally in a distichous (two-ranked) pattern
• Leaf blades measure 30–60 cm long and 10–25 cm wide
• Prominent midrib with parallel pinnate venation characteristic of monocots
• Leaf color varies by cultivar — from bright green to dark green, bronze, or variegated
• Leaf margins are entire (smooth)
Flowers:
• Borne in terminal racemose or paniculate inflorescences
• Individual flowers are asymmetric (zygomorphic), 5–12 cm across
• Typically consist of 3 small, inconspicuous sepals and 3 larger, showy petals
• Petaloid staminodes (sterile stamens modified into petal-like structures) are the most visually prominent part of the flower — vividly colored in red, orange, yellow, or combinations
• Fertile stamens are reduced; the style is petaloid and flattened
• Flowers are primarily pollinated by large bees, hummingbirds, and bats depending on region
Fruit & Seeds:
• Fruit is a warty, ellipsoid capsule, 2–3 cm long, dehiscent (splits open when mature)
• Contains numerous hard, spherical, black seeds approximately 5–7 mm in diameter
• Seeds are among the hardest in the plant kingdom — they can survive passage through the digestive tracts of animals and remain viable for extremely long periods
• Seed coat is exceptionally dense and impermeable, requiring scarification (mechanical or acid treatment) for reliable germination
Canna indica thrives in warm, humid environments and is commonly found in:
• Margins of ponds, streams, and marshes
• Wet meadows and ditches
• Disturbed areas, roadsides, and abandoned agricultural land in tropical and subtropical climates
• Lowland to mid-elevation habitats (typically 0–1,500 m above sea level)
Climate Requirements:
• Prefers full sun; blooms most prolifically with at least 6 hours of direct sunlight per day
• Thrives in temperatures between 18–30°C; frost-sensitive and dies back to the rhizome in temperate winters
• Requires consistent moisture; tolerates waterlogged and even semi-aquatic conditions
Pollination & Seed Dispersal:
• Flowers are pollinated by a range of vectors — large bees, butterflies, hummingbirds, and in some regions, bats
• Seeds are dispersed by water (hydrochory) due to their buoyancy after the hard seed coat is breached
• Rhizome fragmentation is a major means of vegetative spread, particularly in riparian and wetland habitats
Invasive Potential:
• In several regions outside its native range (e.g., parts of Australia, South Africa, Pacific Islands), Canna indica is classified as an invasive species
• Its vigorous rhizomatous growth and prolific seed production allow it to form dense monocultures that displace native wetland vegetation
• Margins of ponds, streams, and marshes
• Wet meadows and ditches
• Disturbed areas, roadsides, and abandoned agricultural land in tropical and subtropical climates
• Lowland to mid-elevation habitats (typically 0–1,500 m above sea level)
Climate Requirements:
• Prefers full sun; blooms most prolifically with at least 6 hours of direct sunlight per day
• Thrives in temperatures between 18–30°C; frost-sensitive and dies back to the rhizome in temperate winters
• Requires consistent moisture; tolerates waterlogged and even semi-aquatic conditions
Pollination & Seed Dispersal:
• Flowers are pollinated by a range of vectors — large bees, butterflies, hummingbirds, and in some regions, bats
• Seeds are dispersed by water (hydrochory) due to their buoyancy after the hard seed coat is breached
• Rhizome fragmentation is a major means of vegetative spread, particularly in riparian and wetland habitats
Invasive Potential:
• In several regions outside its native range (e.g., parts of Australia, South Africa, Pacific Islands), Canna indica is classified as an invasive species
• Its vigorous rhizomatous growth and prolific seed production allow it to form dense monocultures that displace native wetland vegetation
The rhizomes of Canna indica are rich in starch and have been used as a food source in various cultures:
• Starch content of rhizomes can reach 20–25% by dry weight
• Canna starch is notable for having some of the largest starch granules in the plant kingdom (up to 100 micrometers in diameter), making it easy to extract and purify
• Historically consumed by indigenous peoples in the Americas and the Andes; also cultivated as a food crop in parts of Southeast Asia, Oceania, and Australia
• Known commercially as 'Queensland arrowroot' or 'canna starch'
• Rhizomes can be eaten raw, cooked, or processed into flour; young shoots are also edible when cooked
• The starch is highly digestible and has been used as a gluten-free food ingredient
• Starch content of rhizomes can reach 20–25% by dry weight
• Canna starch is notable for having some of the largest starch granules in the plant kingdom (up to 100 micrometers in diameter), making it easy to extract and purify
• Historically consumed by indigenous peoples in the Americas and the Andes; also cultivated as a food crop in parts of Southeast Asia, Oceania, and Australia
• Known commercially as 'Queensland arrowroot' or 'canna starch'
• Rhizomes can be eaten raw, cooked, or processed into flour; young shoots are also edible when cooked
• The starch is highly digestible and has been used as a gluten-free food ingredient
Canna indica is generally considered non-toxic to humans and animals. The rhizomes and young shoots are edible when properly prepared. However, as with many plants, individual allergic reactions are possible. The hard seeds are not toxic but are not consumed due to their extreme hardness.
Canna indica is one of the most popular warm-season ornamental plants in gardens worldwide, valued for its dramatic foliage and long-lasting, vivid blooms.
Light:
• Full sun is ideal — at least 6 hours of direct sunlight daily for optimal flowering
• Can tolerate partial shade but will produce fewer flowers
Soil:
• Prefers rich, moist, well-drained soil high in organic matter
• Tolerates a wide range of soil types, including heavy clay and waterlogged conditions
• Soil pH: 6.0–7.5 (slightly acidic to neutral)
• Can be grown in containers, garden beds, or directly in shallow water (pond margins)
Watering:
• Requires consistent and abundant moisture throughout the growing season
• Can tolerate waterlogged and semi-aquatic conditions — suitable for bog gardens and pond edges
• Reduce watering in winter when the plant is dormant
Temperature:
• Optimal growing temperature: 18–30°C
• Frost-tender; in temperate climates, rhizomes must be lifted and stored indoors over winter (at 5–10°C in dry peat or sand) or heavily mulched in the ground
Fertilization:
• Heavy feeder — benefits from regular applications of balanced fertilizer during the growing season
• Apply a slow-release granular fertilizer at planting and supplement with liquid feed every 2–4 weeks during active growth
Propagation:
• Division of rhizomes (most common method) — divide in spring before new growth begins, ensuring each division has at least one growing eye
• Seed propagation — seeds require scarification (nicking the hard seed coat with a file or soaking in warm water for 24–48 hours) before sowing; germination occurs in 1–3 weeks at 20–25°C
Common Problems:
• Canna leaf roller (Calpodes ethlius or Geshna cannalis) — caterpillars that roll and feed on leaves
• Rust fungus (Puccinia thaliae) — orange-brown pustules on leaf undersides
• Viral infections (e.g., Canna yellow mottle virus) — cause streaked or mottled foliage
• Slugs and snails may damage young shoots
• Japanese beetles may feed on flowers and foliage
Light:
• Full sun is ideal — at least 6 hours of direct sunlight daily for optimal flowering
• Can tolerate partial shade but will produce fewer flowers
Soil:
• Prefers rich, moist, well-drained soil high in organic matter
• Tolerates a wide range of soil types, including heavy clay and waterlogged conditions
• Soil pH: 6.0–7.5 (slightly acidic to neutral)
• Can be grown in containers, garden beds, or directly in shallow water (pond margins)
Watering:
• Requires consistent and abundant moisture throughout the growing season
• Can tolerate waterlogged and semi-aquatic conditions — suitable for bog gardens and pond edges
• Reduce watering in winter when the plant is dormant
Temperature:
• Optimal growing temperature: 18–30°C
• Frost-tender; in temperate climates, rhizomes must be lifted and stored indoors over winter (at 5–10°C in dry peat or sand) or heavily mulched in the ground
Fertilization:
• Heavy feeder — benefits from regular applications of balanced fertilizer during the growing season
• Apply a slow-release granular fertilizer at planting and supplement with liquid feed every 2–4 weeks during active growth
Propagation:
• Division of rhizomes (most common method) — divide in spring before new growth begins, ensuring each division has at least one growing eye
• Seed propagation — seeds require scarification (nicking the hard seed coat with a file or soaking in warm water for 24–48 hours) before sowing; germination occurs in 1–3 weeks at 20–25°C
Common Problems:
• Canna leaf roller (Calpodes ethlius or Geshna cannalis) — caterpillars that roll and feed on leaves
• Rust fungus (Puccinia thaliae) — orange-brown pustules on leaf undersides
• Viral infections (e.g., Canna yellow mottle virus) — cause streaked or mottled foliage
• Slugs and snails may damage young shoots
• Japanese beetles may feed on flowers and foliage
Canna indica has a remarkably diverse range of uses:
Ornamental:
• One of the most widely planted tropical ornamental plants globally
• Used in bedding displays, borders, containers, and water gardens
• Hundreds of cultivars have been developed, including dwarf varieties (e.g., 'Lucifer', 'Tropicanna') and large statement plants
Food:
• Rhizomes are a traditional source of starch in many cultures
• Canna starch (Queensland arrowroot) is used as a gluten-free thickener and food ingredient
• Young shoots are consumed as a cooked vegetable in some regions
Phytoremediation:
• Canna indica is widely used in constructed wetlands and wastewater treatment systems
• Its vigorous root system and high biomass production make it effective at absorbing excess nutrients (nitrogen, phosphorus) and heavy metals from polluted water
• Commonly employed in tropical and subtropical regions for treating domestic and agricultural wastewater
Industrial:
• Starch from rhizomes has been used in the production of biodegradable plastics and adhesives
• Fibers from stems have been explored for paper and textile production
Traditional Medicine:
• In various traditional medicine systems, rhizomes and leaves have been used to treat fever, dropsy, and earaches
• Scientific validation of these uses is limited
Other:
• Hard seeds have been used as beads for jewelry and rosaries
• Historically used as a substitute for lead shot in firearms during the 19th century
Ornamental:
• One of the most widely planted tropical ornamental plants globally
• Used in bedding displays, borders, containers, and water gardens
• Hundreds of cultivars have been developed, including dwarf varieties (e.g., 'Lucifer', 'Tropicanna') and large statement plants
Food:
• Rhizomes are a traditional source of starch in many cultures
• Canna starch (Queensland arrowroot) is used as a gluten-free thickener and food ingredient
• Young shoots are consumed as a cooked vegetable in some regions
Phytoremediation:
• Canna indica is widely used in constructed wetlands and wastewater treatment systems
• Its vigorous root system and high biomass production make it effective at absorbing excess nutrients (nitrogen, phosphorus) and heavy metals from polluted water
• Commonly employed in tropical and subtropical regions for treating domestic and agricultural wastewater
Industrial:
• Starch from rhizomes has been used in the production of biodegradable plastics and adhesives
• Fibers from stems have been explored for paper and textile production
Traditional Medicine:
• In various traditional medicine systems, rhizomes and leaves have been used to treat fever, dropsy, and earaches
• Scientific validation of these uses is limited
Other:
• Hard seeds have been used as beads for jewelry and rosaries
• Historically used as a substitute for lead shot in firearms during the 19th century
Fun Fact
Canna indica seeds are so hard and dense that they were historically used as actual ammunition. During the 19th century, in parts of Southeast Asia and India, Canna seeds were loaded into firearms as a substitute for lead shot when conventional ammunition was scarce — hence the common name 'Indian Shot.' The seeds are also among the few plant materials that have been found lodged in the wheels of early automobiles, causing punctures. Their extraordinary hardness is due to an exceptionally dense, lignified seed coat that is nearly impermeable to water — a single seed can remain viable for decades, even centuries, in the soil seed bank. In some Pacific Island cultures, Canna seeds are still strung together as beads for traditional jewelry and ceremonial objects. The plant's starch granules are the largest known in the plant kingdom — visible to the naked eye as a fine, shimmering powder — and were once used by early microscopists as a calibration standard for their instruments.
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