Saturday, November 26, 2016

Saving Dahlia Tubers in Containers

Step 1: Insulate the Dahlia container in bubble wrap.
Two years ago I dug up my dahlia tubers and kept them all winter at the town condo in the guest bathtub.

The tubers were hard to dig, and needed added moisture in their protective sacks ever few weeks. But, most of them did survive for replanting.

Last fall I tried something different. I wrapped my dahlia containers with bubble wrap and covered the soil with a heavy mulch.

In summer, the dahlias gave me lush plants and beautiful flowers. I would call that a huge success with very little effort.

Step 2: Cut the Dahlias back in fall.
This year I decided to repeat the same procedure.

We don't get extreme cold, but do have several stretches of freezing weather.

I left the bubble wrap on the pots, so that step was already done.

Click here to read more about it. Save the small sized bubble wrap from parcel packaging. You'll have a free supply for winterizing projects.

Step 3: Cover the soil with crumpled newspaper.
The air pockets help keep the freezing temperature away from the sides of the pot, much like an insulated water pipe.

When the weather started turning cold and the foliage died, I cut the dahlia plants back to an inch above the soil level.

I crumpled newspaper over the soil to give the tubers an insulation barrier.

Step 4: Cover the newspaper with a piece of cardboard.
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.

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

This has been a good alternative for me, and I've successfully winterized my rhubarb the same way since 2010.

Step 5: Cover the cardboard with soil to hold everything in place.

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


  1. Great tips, Margy, the dahlias certainly appreciate your efforts!
    I wonder would it work for my outdoor geraniums, as we do have frosts

    1. I sent you an email. My experiments with geraniums outdoors weren't as successful. I did mulch them with newspaper and dirt (no cardboard) and then draped the plants in a clear plastic back with a breathing opening on the back near the cabin wall. I also opened it on sunny days (of which we get only once in a while during winter). The roots that survived weren't as strong as new ones from the nursery. - Margy

  2. Your dahlias are so pretty. I don't have any of them in my yard.
    We get LOTS of freezing weather!

    1. It's important to pick plants based on your climate. But I see lots of dahlias around town planted in the ground. I know some people dig them up to replant in spring. - Margy

  3. Replies
    1. Thank you. I don't have many flowers at the cabin, mostly vegetables so they make a nice focal point. - Margy


Thanks for stopping by. Comments, questions, and suggestions are always welcome. - Margy