Dividing and Storing Dahlia Tubers
Hi Everyone!
Its that’s time of year again, time to dig, divide, and store your dahlia tubers and I wanted to share with all of you how we go about the process here on Campeau Farms. With that being said, we are a small farms and we grow in zone 8b, so depending how we do things here may or may not be exactly how you want to store your tubers, however the processes is mostly the same.
Step 1: Decide if you want to dig your dahlias or let them over winter
We dig our dahlias up each year so that we can divide them in the fall, but you dont have to! In zones 8 and above dahlias can stay in the ground and will over winter just fine with some mulch to protect them.
The main reasons we dig are because we want more plants, and each tuber we planted in the spring multiples and we give us more tubers, which in turn create more plants the next season. However if you dont need more tubers to create more plants and you want blooms earlier you can leave your tubers in the ground. If you do decide to leave them in the ground just make sure you mulch them with some bark or leaves so they have some protection against the cold. If tubers freeze they turn to mush are are not useful anymore.
Step 2: Dig up your dahlias
I recommend using a pitchfork for this step, and you want to start digging about a foot away from the stem of your plant, working your way around it to loosen up the soil.
Once you have loosened up the soil I would try to get your pitchfork under the clump, grip the stem and slowly lift it up.
Once you have it above ground you can gently brush off the dirt.
Step 3: Wash or store your clump
Now that you have your clump dug up you can store it whole with the dirt on it over the winter if you don’t plan to divide it until spring time.
If you choose to hold off on dividing please note that the eyes are a bit easier to see, but the clumps harden and are harder to cut apart. You will want to store the clumps off the ground in a place that wont freeze and stays between 40-50 degrees.
If you do plan on diving in the fall (this is what I do) you will want to wash off your tubers and clean up and tails or tubers with broken necks. Only wash off the amount of clumps you plan to divide within the next 24 hours, otherwise your tubers may begin to shrivel.
Step 4: Divide your tuber clump
For a tuber to be viable it needs to have 3 main parts, an eye, a neck, and the tuber itself. The eye is a small growth node at the top of the tuber near where it attaches to the stem and looks like a little bump, this is where a new plant will grow from so its critical that each tuber has an eye. The neck of the tuber attaches the area where the eyes are to the rest of the tuber which is the new plants food source. If the neck is broken the tuber will rot in storage and needs to be removed.
You will want to take your clump and start identifying where you have tubers with visible eyes, you can then cut these off the clump but make sure its has an eye attached!
I like to only divide one variety at a time and I keep a count of how many tubers I have of each variety after I am done dividing.
Step 5: Store your tubers
Tubers cannot freeze and like to be kept in a dry humid place between 40-50 degrees. I keep mine in our garage and i’ve also heard the basement is a great place to keep them.
I store my tubers in small plastic containers I get from the dollar store. I spread a layer of vermiculite in the bottom of the container, lay tubers on top of that layer, and then cover them with more vermiculite. I repeat this until the container is full or I have no more tubers of that variety. I only store one variety per box so as not to get them mixed up. I then label the box with painters tape and note the variety and number of tubers in the box.
Step 6: Check on your tubers
Tubers are a sizable investment of both money and time so I check on mine over the winter to make sure they are storing well. You want to check for signs of moisture within your storage box, and see if any are starting to rot. If you find boxes with moisture, crack the lid to allow any moisture to escape and remove any rotten tubers. If your tubers look shriveled or dry I would add a few drops of water to the container and close it back up.
After you have successfully stored your tubers for the winter you can plant them back out into the garden once all chance of frost is gone and your soil starts to warm up. To give your tubers a head start you can start waking them up a few weeks early by bringing them into the house, or pre-sprouting them on a heat mat in some soil. Both of these techniques will give your tubers a little head start in the spring time.