To dig or not to dig…your dahlias
Ah, the age-old gardener’s dilemma here in Victoria, BC….are you ‘supposed to’ dig up your dahlias each year? As with almost all gardening advice, it depends.
We are in Zone 8b here on the southern tip of Vancouver Island, which is mostly mild and is a gardener’s dream climate because you can be growing things year round. The ground (almost) never freezes. That means it’s almost harder to decide because you could go either way!
Below, I’m sharing a few reasons for why you might want to do either option. You’ll also see a list of what you would need to do if you choose to dig…or not to dig…so you know what you’re getting yourself into. Once you’ve got all the facts you can decide on your next steps.
Here’s why you might want to dig them up:
To prevent the loss of tubers in the ground over winter due to either freezing or sitting in boggy, wet soil. In either case, they will likely rot if you leave them where they are. *Normal, well-draining garden soil where no water pools should be fine if well-mulched over winter.
To move them to another location next season.
To divide a big clump and multiply your number of plants for next year.
What to think about before digging them up:
Where will you store the tubers?
It needs to be cool (under 10c), but not susceptible to freezing, and the humidity level should be 80%. An insulated shed, basement closet, or garage would work.
The tubers need to be stored in containers with a medium of some kind (wood shavings, vermiculite etc.) to help prevent rot. This is messy…do you want it in your spare room closet?
Are you going to wash them and divide them for storage right away, or store them as is with the soil to divide later?
First option means doing it within a week of digging them up so they don’t begin to shrivel up. Wash the clumps, trim the tails, divide the tubers, let them dry again and then wrap/store with your preferred method.
Second option means washing and diving them later…like after Christmas when you can breathe again. You’ll need a container to put these awkwardly-shaped soil-covered tuber clumps that is breathable, and a spot to keep them that’s dirt-friendly and won’t freeze.
Do you actually have the time to complete this task?
Once your clumps have been dug up (easy part), you will need to deal with them (hard part). If you’re planning to divide them, this is a multi-day process with quite a few steps, and they need to be kept cool until you’re ready.
Altogether (not including the overnight drying), the average time needed to dig, wash, trim, divide and store one clump of tubers is about 90 minutes, plus the time it takes to set up your tools and clean up afterwards….and acquire the tools and containers and medium in the first place….do you see where I’m going with this?
Here’s why you might NOT want to dig them up:
You won’t have to do all of the above steps!
You don’t have the storage space needed.
You don’t care about dividing the tubers.
You’re happy where your plant is and are sure it’s in well-drained soil.
You’re a risk-taker who’s willing to see what happens!
Here’s what to do if you DON’T dig them up:
Buy more tubers from Bowker Creek Flower Farm ‘just in case’….lol
Cut the stem of your plant all the way down to the crown (top of the clump). This will prevent water pooling in the open stem and leaking into the tuber clump causing rot and making them more susceptible to freezing.
Put a labelled stake into the ground to mark the spot (if you want to). Sharpie on flagging tape will last throughout the winter.
Cover the plant with a very thick layer of leaves as a mulch…like 8-10”.
In early May, pull away the mulch to use elsewhere, apply 2” of compost and organic fertilizer, put in your plant support and wait for those first sprouts!
Note: It only takes one viable tuber to make a plant! If the plant you leave in place has a clump with ten tubers on it and only one survives the winter, you’ll still get a strong and healthy plant full of flowers in the summer. It’s worth a try right?
So? Are you going to dig up your dahlias or leave them where they are?
I don’t know about you, but I really like to understand how much time and effort something will be before I get started. I hope this info helps!
At the end of the day, try not to worry too much about it, just make a decision and see what happens. The beauty of gardening is that your decisions are mostly pretty low-stakes and you can always start again right?
I’d love to know what you decide! If you’re still confused and have a question please drop it below and I’ll try my best to answer.
Happy November Gardening!
xo - Renée
