The secret to successfully growing dahlias in cooler climates lies underground in their tubers.
During the growing season, each dahlia plant produces a clump of tubers up to six inches deep underground.
Dahliatubersare not true bulbs.
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Dahlia foliage cannot tolerate freezing temperatures.
The first heavy frost will blacken and turn to mush the flowers, stalks, and foliage.
Don’t be too hasty and dig your tubers before the first frost.
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Frost stimulates dahlia tubers to set eyes for next year.
Be careful not to let tools come in contact with the tubers, which are easily damaged.
Gingerly pry up the soil as you go, freeing the tubers.
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Dont save every tuber, save only tubers that are in good condition.
Clean off most of the soil and trim back the roots.
It’s important to remove and discard the mother tuberit’s located in the center part of the structure.
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The mother tuber produced the plant this year and wont have any more energy left for next year.
In the case of first-year plants, this is the original tuber that you bought and planted.
The mother tuber is more likely to rot and could spread to the other tubers in storage.
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Dividing means cutting apart the crown and retaining one or more tubers along with it.
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In this case, it can be more time-efficient to wait until spring to divide the tubers.
Only cure them outdoors if temperatures are above freezing.
If rain is forecasted, move the tubers indoors to a location that does not receive direct sunlight.
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Once the dahlia tubers are dry, use pruners to remove most of the remaining stalk.
Sprinkle the tubers liberally with sulfur dust.
Take care to apply the powder to any areas that are nicked or cut.
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Prepare the Storage Box
Line the bottom of a cardboard box with newspaper to cover any cracks.
Pour in two inches ofpeat moss.
Use a spray bottle to slightly moisten the peat moss.
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confirm not to saturate the peat moss, which can cause tubers to rot.
Instead, strike a balance between dry and wet, erring on the side of dry.
Storage medium
Tuber storage medium is a matter of debate.
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Instead of peat moss, some gardeners opt to usevermiculiteor even dry sawdust as their tuber storage medium.
Other gardeners individually wrap each tuber in newspaper.
Still others wrap tubers in plastic wrap.
The Spruce / Jayme Burrows
The point is that there is no single answer for storage medium and methods.
you oughta experiment with what storage process is successful for you year to year.
confirm tubers or tuber clumps are not touching one another.
it’s possible for you to place dry sheets of newspaper between layers of tubers.
The ideal storage temperature is above freezing but below 50 degrees Fahrenheit.
Check the Tubers Periodically
Periodically check your tubers during the winter.
If they seem overly dry, spritz the peat moss with a spray bottle.
And if a tuber feels mushy, discard the rotten culprit before it infects the rest of the tubers.
Then, the tubers are ready to be stored.
You might even consider using separate storage boxes for each dahlia variety.
Digging, Dividing, and Storing Tubers.The American Dahlia Society Website
