It’s time to put tropical and tender bulbs to bed for the winter, including dahlias, caladiums, cannas, and elephant ears. All of these bulb-based plants are actually quite easy to overwinter.
My very favorite is the Colocasia or elephant ears. There are several ways to over-winter these beauties. Option one, is to dig them up now that we’ve had a killing frost. Cut the foliage above the bulb, leaving about 5 to 6 inches. Lay them in a area (where they won’t freeze) to dry for a week or two. If you put them away wet, they’ll rot. Once dried, place them in a cardboard box either on their own, or on top of some peat moss, wood or paper shavings. Store them with the box lid ajar for air circulation in a cool, dry place. Option two is to leave them in their pot, cut the foliage down, and store the entire pot in a cool, dry location. Option three will work if the foliage is still intact. Just them in a sunny window, treating them like a houseplant. Water sparingly if left in pots.
I’m going to sound like a broken record, but since we’ve had a killing frost, cut back Cannas to within 4 to 6 inches from the ground. Carefully dig up the canna clumps with a spade or garden fork, leaving a small amount of soil around the cannas. Allow them to dry for a few days in a heated area. Once dry, place them in large boxes, wire crates or in mesh bags and store them in a cool, dry location and it’s OK if there’s still soil around them as long as it’s dry.
Dahlias too are ready to dig when darkened by frost. Cut them back to within 2-4 inches of the ground and carefully dig up the tuberous roots with a spade, you do want to remove all the soil from dahlias and let dry. Divide these now after digging since the "eyes" or "buds" are easier to see in the fall. Once dry to the touch, store the tubers upside down in vermiculite in a dry, cool location.
Caladiums and Calla Lilies require the same treatment, cut back the foliage to an inch or two, lift the rhizomes out of the soil, and dry both of them for about two weeks. Then store in vermiculite or peat moss in a cool, dry place.
Periodically check your stored bulbs, tubers & rhizomes for any signs of mold or rot and discard those right away. In the Spring you can either pot these up early inside or plant directly outside once the soil temperatures are sufficiently warm.
Written by Lisa Slattery, Annuals Manager