Homegrown: Storing tropical bulbs over the winter

The following is by Iowa State University Extension & Outreach, Linn County Master Gardener Lisa Slattery

 I spent this past weekend digging and prepping my tropical bulbs for winter storage.  I've had mixed luck in the past with overwintering various bulbs, including tuberous begonias totally drying out and having cannas rot.  Mostly likely due to neglect on my part. 

 This year I have elephant ears (Colocasia esculenta) that I'm going to overwinter.  Mine were show stoppers this year with huge, beautiful, heart-shaped leaves and I want them for next year.  Dig these up after a killing frost, cutting the foliage off first before digging.  These bulbs need to sit in a warm, dry location for one or two weeks.  After letting them dry, bury the bulbs in a box with peat moss or wood shavings and store them in an area with a temperature of 70 to 75 degrees F.

I have several varieties of cannas that I also dug this weekend.  Again, wait until a hard, killing freeze and then cut back the plants to within 4 to 6 inches of 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 several hours and then place them in large boxes, wire crates or in mesh bags and store them in a cool (40 to 50 F), dry location.  

Cannas and Elephant Ears are the only tropical bulbs I save from my garden but there are several other favorites that gardeners like to overwinter including gladiolus and dahlias.  

Glads should be dug up a little earlier in the fall or even in late summer.  Remove the soil from the bulb-like corms and cut the foliage to within 1 to 2 inches above the corms.  Dry the corms for two to three weeks in a warm, dry, well-ventilated location.  When totally dry, remove the old, dried up mother corms located at the base of the new corms as well as the tiny corms (cormels) found around the base of the new corms.  Place the ones you're keeping in mesh bags or old nylon stockings and hang in a dry, well-ventilated location that stays between 35 to 45F.

For Dahlias, cut them back after a killing frost to within 2-4 inches of the ground.  Carefully dig up the tuberous roots with a spade, shaking off the soil and cutting the stems back to the crown.  Wash these bulbs to remove any remaining soil and allow them to dry for about 24 hours.  After they dry, place the dahlia clumps upside down in boxes, covered with vermiculite, peat moss or wood shavings.  Store in a dry, cool (40 to 50F) location.

How many bulbs you dig up for overwintering is determined by.....How much time and energy you have left for gardening in late Fall.....How much space can you devote to storing bulbs..... And, how cheap are you when it comes to replacing them in the Spring....

I won't mind if I lose a few cannas this winter, but I'll take very good care of my elephant ears!