Red cannas are perennial tropical and subtropical lilies that grow from 1 1/2 to 5 feet tall. They have large, glossy green leaves ranging from 6 to 12 inches wide. In areas where the temperature drops below 10 degrees F, red cannas will not overwinter. These flowers need much care and attention. Knowledge of how to create the right environment for the plant will keep it healthy and blooming.
Plant canna rhizomes 3 to 5 inches into the ground, horizontally, with eyes facing upward. Choose an area with full sun and rich, well-drained, loamy, nutrient-rich soil. Mix in 2 inches of rotted manure right before planting to increase nutrient value of the soil.
Water the rhizome, keeping the soil moist until it starts to grow. In dry weather, water deeply once a week.
Fertilize red cannas monthly after planting. Cannas are heavy feeders, and this encourages blooming. Use a complete fertilizer, but avoid feeding it excess nitrogen. Look for a fertilizer where the first number, representing nitrogen, is less than the second two numbers, representing phosphorus and potassium. Follow the directions on the package for application instructions.
Remove the blooms as they fade on the stem. This will encourage flowering throughout the summer.
Cut the stems back to 2 to 3 inches after the first frost in cooler regions where the canna will not overwinter. Dig up the rhizomes with a spade, keeping a small amount of dirt around the rhizome. Dry them for a week, and then store them in a cool area, such as a basement, for the winter. Replant the rhizomes in the spring.