Saving Summer Bulbs – Cannas and Dahlias
Nobody talks much about it, but the truth is the damn things tend to multiply.
In the space of a single summer, one wizened little dahlia tuber can become a clutch of potatolike lumps the size of a basketball and the cannas are even worse – or better, if you’ve got a spot that could use a mass of something. Just because they got overused in the days of carpet bedding shouldn’t consign using cannas as hedging to the dustbin of horticultural history.
This is by way of saying that – assuming you’ve got room in the cellar or garage – too much of a good thing may be just enough. And of course a bit more of an expensive thing is its own kind of gratification.
To Save Cannas and Dahlias Over Winter In Cold Climates.
1. Wait for the frost to kill down the tops. Expert opinion is divided on the necessity for this, but in my experience the unpleasant shock does seem to encourage the rhizome to think good thoughts about dormancy.
2. Choose a dry day to dig them up. Do so. Allow the dirt to fall off, and let the surface dry if it’s wet. (Some people wash and dry them, then dust with fungicide. I don’t.)
3. Clip off the dead stems, leaving a stub about 2 inches tall; there can be incipient buds underneath. Cut off any chunks of rhizome that are obviously diseased, but other than that leave them alone.
Again, the experts are divided. Some say this is the time to cut off dead sections and divide the good parts, but by me the fewer wounds there are, the fewer chances there are for needed moisture to leave or unneeded rot to enter.
4. Line a thick black plastic garbage bag or plastic storage box with a layer of light, air-holding insulation – peat moss, coir, pine needles, or packing peanuts – just deep enough to cradle the rhizomes and cover them thinly. Nestle the rhizomes into it, right side up and not touching.
5. Store in a cool but not cold place, 45 -50 degrees is ideal, five more degrees either way won’t make much difference. Leave the top partially open or partially cover, as the case may be, so moisture is held in but not trapped.
Check every month or so, opening the bag/cover a bit more if the rhizomes look sweaty, sprinkling very lightly with water if they appear to be drying out. Some of the buds may show signs of growth. No worries; they usually proceed very slowly; just try to avoid breaking them off.
Same routine as the cannas, except:
1. Cut the dead stems off short, about ½ inch long. The incipient buds are nestled at the neck of each tuber where it meets the stem and any extra stem will simply rot if it doesn’t dry out.
2. If the clump is at all sizable, there will be dirt trapped between the tubers. I ( or as often as not Kristi) turn the clumps upside down and let them dry off before removing any rotten tubers and proceeding toward storage.
Sometimes the clumps fall apart into smaller clumps or an individual tuber may separate from its fellows. No problem. Unless you count
Labeling, the curse of dahlia storers everywhere.
Over the years I have tried:
1. Putting each variety in a labeled brown paper bag before nestling in the insulation. Works pretty well if the bags don’t disintegrate.
2. Writing with sharpie right on one or more of the tubers in each clump. Works fine if the writing doesn’t fade and the tubers stay clumped.
3. Writing on a plant label and pushing the point between a couple of close tubers or stabbing it into a stem. Again, works fine “if “– in this case if the label doesn’t fall out into the general mass.
4. Writing on a strip of flat plastic plant tape and tying it to one of the stems. This is Kristi’s preferred method and therefore the one in current use. Works pretty well, in part because at this point we have so many tubers each variety can have a private section of the storage box.