Things You'll Need
Water-soluble 5-10-5 fertilizer
Cut the spent foliage and flowers down to the ground in November, or after the plant completes its blooming cycle, in U.S. Department of Agriculture plant hardiness zones 7 through 10. Cover the pruned plant with 10 to 12 inches of organic mulch; sphagnum peat moss, composted pine bark or leaves work best. Outside of these hardiness zones, dig up canna lily rhizomes and store them in a cool, dry location. Replant the rhizomes the following spring after the threat of spring frost has passed.
Pests such as canna leaf rollers, thrips, spider mites, slugs and snails damage Canna lilies. Treat minor infestations by rinsing the foliage in a directed stream of water or by hand-picking slugs or snails from the plant. Use a garden insecticide to curtail more serious infestations.
Known botanically as Canna X generalis, canna lilies are rhizomatous, perennial herbaceous plants that bloom best in warm climates such as those found in U.S. Department of Agriculture plant hardiness zones 8 thorough 11. Gardeners living outside of these zones may also enjoy canna lilies' attractive ovate leaves and showy blossoms by removing the plant's rhizomes from their garden after they've completed their blooming cycle. With the proper care, canna lilies are capable of blooming continuously from midsummer until the first fall frost.
Plant your canna lilies in a full sun location to ensure a long and productive blooming cycle. Canna lilies perform best in sites that receive at least six hours of direct sunlight per day. Plant canna lily rhizomes 3 to 4 inches deep in a prepared garden bed; when planting multiple rhizomes, space them 2 to 3 feet apart.
Irrigate canna lilies weekly while the plants are actively growing and flowering. Provide 1 to 1 1/2 inches of supplemental irrigation each time you water; canna lilies bloom best in moist, well-draining soil.
Fertilize canna lilies in early spring with a water-soluble 5-10-5 fertilizer, applied according to label instructions. Apply subsequent fertilizer applications at the beginning of each month to keep your canna lilies blooming all season long. Cease fertilization just before the first fall frost; resume your regular fertilization schedule the following spring.
Deadhead canna lilies throughout the growing season to keep them blooming for as long as possible. Cut spent blossoms from your canna lilies with sharpened and sterilized garden shears; this stimulates canna lilies to produce another round of blooms.
- University of Minnesota Extension; Calla and Canna Lilies; Beth R. Jarvis; February 1999
- University of Florida Cooperative Extension Service; Canna x generalis; Edward F. Gilman; October 1999
- Floridata; Canna X generalis; Jack Scheper; July 1998
- University of Arkansas Cooperative Extension Service; Canna Lily; Gerald Klingaman; July 1999
- Alabama Cooperative Extension System; Canna Lilies for Alabama...; J. Raymond Kessler; July 2007
- Arizona State University: Canna x generalis
Megan Mattingly-Arthur has been writing professionally since 1998. She has contributed to various publications, including "Teen Voices" and "Positive Teens" magazines, as well as a book, "The Young Writer's Guide to Getting Published." Mattingly-Arthur is studying travel and tourism through Penn Foster Career School.