The canna may rot if left unprotected in freezing conditions, but it is a perennial plant in temperate zones; it does well with moderate water in well-drained rich or sandy soil and is largely free of pests. In areas which go below about 5°F (-15°C) in the winter, the rhizomes (horizontal roots, not unlike those of a potato) can be dug up before freezing and stored in a protected area for replanting in the spring.
The flowers attract hummingbirds. The plants sometimes fall victim to Canna leaf rollers, or Brazilian skippers, the larval stage of a butterfly which cuts the leaves and rolls them over to live inside while pupating (the lesser canna leaf roller will sew the leaves shut before they can unfurl). Affected leaves can be cut off and destroyed or unrolled and cleaned (removing the caterpillar), though some gardeners prefer to use Bacillus thuringiensis, insecticidal soap, or the chemical malathion to kill the pests. In areas with a freezing winter the leaf roller is not typically a pest.
Cannas may also fall victim to canna rust, a fungus resulting in orange spots on the plant's leaves. Rust infestation is facilitated by overmoist soil.
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