Canna rhizomes are beautiful, lush tropical plants typically found in Hawaii, California and Florida year-round. They have tall stalks with big leaves and bright blossoms that humming birds love. There are different varieties with patterned and multicolored leaves and various colored blooms. Although they grow best in tropical climates, it is possible to grow them in many regions after the last frost of the winter. They are well suited for the back of flowerbeds because of their tall stature or in a place all their own.
Find a spot for your cannas in a full sun area. Till the soil to a depth of 12 to 15 inches and mix in a 3-inch layer of compost.
Cannas are tubers that need to be planted in the spring after the danger of frost has passed. Dig a hole 4- to 6-inches deep in the tilled soil and set the rhizome tuber horizontally in the hole. Cover the tuber with soil and pat firmly. It is important to space the tubers 2- to 3-feet apart because they grow lush and full.
In areas where there is a long winter, you may start the cannas indoors by potting them and placing in a sunny, warm location. Once the danger of frost has passed, replant them outside.
Once planted in the ground, apply a 2- to 4-inch layer of mulch on top to help retain moisture and control weed growth. Fertilize with a nitrogen rich fertilizer once a month. Cannas like moist, well-drained soil, but be careful not to over water. Stake the stalks to keep them upright once they begin to grow.
In the fall after the first frost, cut back the stalks and lift the clumps of tubers out of the soil. Place them into a plastic bag until next spring. Store them in a dry cool area.