Garden Tip 216

Canna lilies make striking garden accents, create bold mass plantings, and add dramatic height and color to mixed containers. Grown from bulb-like underground stems called rhizomes, cannas feature large, paddle-shaped foliage and tropical-looking flowers on plants that can reach up to seven feet tall. Depending on the variety, their foliage may be green, bronze, nearly black, or beautifully variegated.

Cannas multiply readily as their rhizomes expand each growing season, so a single planting can quickly become a spectacular display. In Massachusetts, however, canna rhizomes are generally not winter hardy and are typically dug up in the fall and stored in a cool, dark place until spring.

At Highfield Hall, we’ve discovered an exception to this rule. A vibrant stand of cannas grows in a garden bed against a south-facing stone wall. One spring, as we prepared to replant the rhizomes we had lifted the previous fall, we found that several rhizomes left behind had survived the winter and were already sending up new growth.

That discovery was four years ago. Since then, we have left the rhizomes in place, and each spring they emerge to create an increasingly spectacular display. The warmth absorbed and radiated by the south-facing stone wall appears to provide just enough protection for the rhizomes to survive the winter.

If you have a sheltered location with a south-facing stone or brick wall—or even a sunny house foundation—you may be fortunate enough to discover that your cannas can behave like perennials, too.