How to Winterize Canna Lilies in Cold Climates

Overwintering Canna Lilies: A Step-by-Step Guide

If you live in a region with harsh winters—like Eastern Washington's high desert—you can still enjoy canna lilies year after year. These tropical-looking plants thrive in containers during the hot summer months, but they need proper care to survive freezing temperatures.

When to Dig Up the Rhizomes

Wait until after the first frost has blackened the foliage. This signals the plant to enter dormancy. Cut the stems back to about 4–6 inches above the soil line, then carefully lift the rhizomes from the pot or ground, shaking off excess soil.

Curing and Storage

Allow the rhizomes to air-dry in a warm, well-ventilated spot for about a week. This toughens the skin and reduces rot risk. Once dry, place them in a cardboard box (never plastic bags) with plenty of airflow. A cool, dark, humid location—like an unheated basement that stays above freezing—is ideal. If your garage drops below freezing, it’s too cold; the rhizomes may rot or desiccate.

Optional Medium

Some gardeners nestle rhizomes in dry peat moss, vermiculite, or sawdust, but this isn’t strictly necessary. The key is consistent cool temperatures (40–50°F), darkness, and good ventilation.

Expect Some Loss

Don’t be discouraged if a few rhizomes don’t make it the first year. Overwintering is a skill that improves with practice. Come spring, replant after all danger of frost has passed, and you’ll be rewarded with another season of bold, colorful blooms.