Growing Cannas
Is it OK to leave canna lilies in the ground over winter? And when they are done blooming what are the funky looking little balls where the flowers used to be? They are filled with very hard black balls. Are these, or any part of the plant poisonous?
Canna lilies are hardy in zones 8 to 11. That means gardeners in colder zones need to treat them like annuals or move them indoors for winter. Northern gardeners can save their cannas from year to year by storing the rhizome, thick fleshy root-like structure, in a cool dark location. Dig the plant in fall after a light frost. Set it in a warm dry place to cure. Gently remove any soil and cut off the foliage. Pack in peat moss or sawdust and store at 45 to 55 degrees.
The funky looking balls are seed pods. The hard round things inside are seeds. These black seeds are so hard that the West Indies natives used them as shot giving these plants another common name Indian shot. One of the ornamental cannas’ relatives the Queensland Arrowroot (Canna edulis) was used as food and is an ingredient of arrowroot starch. I wouldn’t recommend munching on your cannas but I could find no reference stating they were poisonous.
Related
Upcoming
Events & Webinars
April 23, 2026
Iowa State University
More information
April 25, 2026
Pasquesi Home & Gardens
Lake Bluff, IL
April 26, 2026
Ebert's Greenhouse Village
Ixonia, WI
May 2, 2026
Ebert's Greenhouse Village
Ixonia, WI
May 6, 2026
FREE WEBINAR:
Adding Native Plants
to Any Size Gardening Space
Register here
May 7, 2026
Wauwatosa Public Library
Wauwatosa, WI
Register here
May 9, 2026
Ebert's Greenhouse Village
Ixonia, WI
May 10, 2026
Ebert's Greenhouse Village
Ixonia, WI
May 13, 2026
Roots & Branches
West Bend, WI
Register here
May 16, 2026
Ebert's Greenhouse Village
Ixonia, WI
May 17, 2026
Ebert's Greenhouse Village
Ixonia, WI
May 20, 2026
Herb Container Workshop
Pewaukee, WI
Register here
May 21, 2026
FREE WEBINAR:
Planting & Care of Your Rain Garden
Register here
June 3, 2026
FREE WEBINAR:
Managing Your Landscape
with Pollinators in Mind
Register here
June 10, 2026
Enjoy Life Active Aging Symposium
Brookfield, WI
More information
July 9, 2026
Ebert's 50th Anniversary Celebration
Ixonia, WI
August 6-16, 2026
Wisconsin State Fair
We Energies Energy Park, West Allis, WI
Sept. 3, 2026
FREE WEBINAR:
Tree Planting and Care
Register here
Sept. 12, 2026
Knowledge in Bloom Conference
Milwaukee, WI
Register here
Sept. 17, 2026
FREE WEBINAR:
Fall Landscape Care and Planting
Register here
WATCH ON-DEMAND WEBINARS
MORE UPCOMING EVENT DETAILS


