Using potting soil mediums for canna storage should be ok providing it is kept slightly moist to prevent your rhizomes losing moisture: do not keep soggy wet; keep as cool as possible. Some of our potting soil mixes contain additives that I do not think aids in the storage cycle. Often gardeners will use potting soil and pot their cannas for winter storage and usually do just fine. Peat is typically recommended because it seems to have some natural bacteria and/or fungal inhibitors.

I may be misunderstanding part of your question: are you suggesting that you want to continue to save the cannas dug in 2013 and stored in the basement until 2015? I sure would like to know if you have checked these cannas to see how viable they really are. Very few people have successfully dug and stored cannas for two years before planting with much success. If you succeed I sure would like to know more about your storage conditions and which cultivar (variety) you are growing.

As for rinsing off the canna clumps before storing: usually not a problem if you delay severely dividing the clump until closer to planting time.

Kent

Thanks Kent!

I live in Missouri next to Illinois, I have been growing cannas for the last 7 years. Through research I have a method for over wintering my canna rhizomes that has never failed me. I dig them up after the first frost has killed off the foliage, trim the stalk to about 2 inches, rinse off all dirt/mud from them, check for any damage or signs of disease,(cut away any yuck) and place them on a rack to dry with a fan on low to dry them. After about a day of drying, I then place them on top of dry potting soil in cardboard boxes (no lids, open to the air) and give a mist of Fungcide, and will typically keep a small fan blowing for circulation throughout storage in a cool dark corner of the basement. Every few days I check them and give them a mist of water. I am pretty medothical about making sure that any soft foliage dries so as to not promote fungal infection that will turn them to mush by spring. Last winter I tempted fate and did not dig them up, the winters had been mild for years. I mulched them and Well, last winter we had record snow fall and lots of moisture. I lost half of my collection, they were mush. Only the rhizomes closest to the foundation of my house made it. Happy to report that the ones that did make it grew and flowered beautifully :)

Lisa,

Thanks for the input. Just for the record, what would you say your average temperature is in your cool basement?

Kent

I store them in the unfinished area of our basement, so maybe somewhere in the 60's?

I've tried several ways of storing cannas over the years and the best way I've found is lining a cardboard box with plastic, digging the tubers with a clump of dirt and putting them in the box with the dirt. If there are tubers without dirt I just add a little dirt to cover and store them in the cellar. I give them a little water about once a month except last year I didn't water and lost most of them!

okay another 2 cents on storage. Mid Michigan. Last winter was too long and too cold. Killed lots of stuff, and damaged lots. I keep my Calla and Canna bulbs in my garage in my try-level. Control of temp. is difficult, when family leaves garage door open to shovel snow. My bulbs were pretty sad, dried out too much, but they grew really well this summer! Had a bumper crop. Anyway I usually wash them off a bit, dry them if weather permits, store in cardboard boxes with some newspaper, sprinkle boric acid powder all over them, store off the floor on a rack. Try to check once a month and sprinkle them with water. With more room I would drape the whole lot with a black plastic sheet to eliminate light, and to protect of bit more from the cold.

I left mine in the spot that they grew and covered with thin tarp and they all came up this past Spring and they had put on a show in a 3 x 3' space. In the Spring as they were appearing, I pruned some of those that kept coming up to allow about 8 to grow. I will do the same thing this Fall. The problem with Canna's they keep having 'babies'...LOL BTW, I live in the NYC area for those who wonder.