Canna lilies are perennial flowering plants that thrive in the heat. Perfect for the tropical-themed garden, cannas are known for their striking, multi-colored foliage and large blooms in shades of orange, yellow, red and pink. They require lots of water, so if you live in an area with low rainfall, you may need to water them twice weekly during particularly hot periods. Plant your canna rhizomes in the spring, after the danger of frost has passed.
Choose a planting site that receives sun for at least four hours a day, although all-day sun is preferable.
Add soil amendments to the existing soil in the planting area. Three to 4 inches of compost or well-rotted manure is ideal. Mix the amendment into the top 10 inches of soil, using a shovel or gardening fork.
Dig planting holes that will allow the canna rhizomes to be covered with 2 inches of soil. Space the holes 12 inches apart. Canna rhizomes don’t have a top or bottom, so plant with either end in the hole and it will grow.
Water the canna bed until the soil is very wet and then keep the soil moist, not soggy.
Spread a 3-inch layer of mulch on the soil around the base of the plant when it sprouts. Mulch conserves soil moisture and discourages weed growth.
Fertilize the canna once a month using 5-10-5 fertilizer at the rate of 3 lbs. for every 100 square feet of planting area. Water the soil prior to fertilizing and follow the directions and warnings on the fertilizer package.
Remove the flowering stem when the flowers die. This will encourage the plant to produce new flowers instead of seed, which signals the plant to stop blooming.
Cut the canna back to within 1 inch of the soil in the fall when the foliage begins to yellow. Carefully pry the rhizome from the soil and place it in a dry, cool area for three hours or until it is completely dry.
Place enough dry vermiculite or peat moss to completely envelop the rhizomes in a box. Push the rhizomes into the material until they are covered. Don’t allow the rhizomes to touch one another. Store the box in a cool (40 to 50 degrees F), dry area. Replant the canna in the spring, after the danger of frost has passed.