Answer: Cannas are tropical plants and will not tolerate any frost on their tips at all. To get a head start, many gardeners start them in pots (set the rhizome about an inch or two under the soil surface) and set them in a sunny spot (do not allow them to get cold at night if you set them outdoors during the day) to root and sprout before planting them in the garden after all danger of frost and the soil has warmed. Larger rhizomes will produce larger, earlier blooming plants but in general they start to bloom in mid summer and will continue until frost. They do best in a deep rich moist soil in full sun.
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