Canna lily
Botanical Name
Canna indica
Family
Cannaceae (canna lily)
Also known as
Indian shot
Where is it originally from?
Central and South America
What does it look like?
Erect, leafy perennial herb (<2 m tall) with thick underground stems (rhizomes) and sturdy, unbranched, green and hairless above-ground stems from which large, green (sometimes purple tinged), oblong leaves (<45 cm long x 15 cm wide) with prominent midribs grow. Pinkish-red to reddish-yellow and occasionally yellow or orange-red flowers (5-6 cm long) grow from the top of the stem, often in pairs, followed by round seed capsules (2 cm diameter) containing round black seeds.
Are there any similar species?
Hedychium gardnerianum (kahili ginger, wild ginger) and H. flavescens (yellow ginger)
Why is it weedy?
Forms tall, dense, long-lived stands that are tolerant of a range of conditions including salt, wind, grazing or other damage, and damp to moderately dry conditions.
How does it spread?
Seeds are spread by gravity and water, and pieces of underground stem (rhizome) also form new plants.
What damage does it do?
Replaces all other plants on the ground, preventing natural regeneration, often leading to the invasion of weedy vines. Removes water from damp habitats.
Which habitats is it likely to invade?
Damp sites with high light in frost-free localities: wetlands, river margins, gullies, disturbed shrublands, forest margins, coastal areas.
What can I do to get rid of it?
1. Physical removal - Hand pull or dig out entire plant (all year round) - Ensure all plant material is removed from site to prevent regrowth. Mulch leaves and dispose of to a refuse transfer station.
2. Cut and paste - Cut the stem as close to the ground as possible and cover the entire stump with herbicide as soon as possible after cutting. Apply a glyphosate + metsulfuron gel mix or picloram gel (43g/l strength) to the entire cut stem.
3. Foliar spray - Apply herbicide using a hand held sprayer/knapsack. Apply a mix of Glyphosate (360 g/L active ingredient) herbicide at 15ml/L + metsulfuron herbicide (600g/kg active ingredient) at 0.3g/L + an organo silicone penetrant such as 'pulse' or 'boost' at 1ml/L and thoroughly wet all parts of plant. Note: Overspray will kill other (desirable) broadleaf plants and has residual activity in the soil which aids in killing below ground parts. Do not use over or near water bodies or wetlands and use only as directed on label.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Fragments remaining in soil will resprout so followup control by digging or spraying is required. Plant the site with local native plants to shade out seedlings.
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