Saving Dahlia Tubers in Pots

Step 1: Wrap the pot in bubble wrap.

A year ago I dug up my dahlia tubers and kept them all winter long in town in my spare condo bathtub. The tubers were hard to dig up, and needed added moisture in their protective sacks ever few weeks. Most of them did survive for replanting.

Step 2: In fall cut back to a few inches.

Last summer the dahlias gave me beautiful flowers, but I wanted an easier way to save them.

So last year I tried keeping the the tubers in their pots. We don't get extreme cold, but we do have freezing nights, and several stretches of freezing weather.

Step 3: Crumple newspaper over the soil.

I started by wrapping the pots in bubble wrap I purchased at the Dollar Store. Each pot got $2 worth of bubble wrap held in place by duct tape. My thinking is that the air pockets will help keep the freezing air away from the sides of the pot, much like an insulated water pipe.

Step 4: Place cardboard over the newspaper.

When the weather started turning cold, I cut the dahlia plants back. I crumpled newspaper over the soil to give the tubers an insulation barrier. Over the top of the newspaper I put a layer of cardboard, and topped it off with soil to keep everything in place on windy days.

Step 5: Cover with a thin layer of soil.

I don't have any place to bring the pots indoors at the cabin where temperatures won't get below freezing sometime during the winter.

Have you ever kept dahlias outdoors through the winter? Do you get freezing nights? Was it successful for you?

Dahlia tubers in pots ready for winter.

My overwintering experiment was a huge success. Here are the results for my two pots.

Pot #1

Pot #2

The bubble wrap is still on the pots and ready to go for next winter. All I have to do is cover the tops again for next winter. This was so much easier than digging up all the tubers and storing them in my bathtub. -- Margy