Gardening chores may be over, but if you haven’t dug out your dahlia tubers yet, there’s one more job to do. The dahlias, which are native to Mexico, don’t survive a hard freeze (24 degrees or below), so you may want to do it soon.
Here are tips for how to dig up the tubers and store them for winter, courtesy of the National Garden Bureau.
Step 1: Dig them up.
- Cut foliage back, so that only a couple of inches remain above ground.
- Take your preferred digging shovel and dig around the tubers, being careful not to accidentally sever the roots. Many gardeners use a pitchfork to prevent this from happening.
- Once you’ve dug the tuber up, shake the dirt off and set aside.
- Repeat until you’ve dug all of your tubers up.
Step 2: Wash off dirt.
After you’ve dug all of the tubers up, gently wash the dirt off in a tub of water, or with a garden hose. Make sure not to puncture the skin of your tubers, as this could cause them to rot over the winter months in storage.
Step 3: Examine the tubers and divide as needed.
After you’ve rinsed the tubers off, it’s time to examine each clump to make sure that there are no rotten parts. If there are, cut these bits off.
If the tubers have several eyes, you can divide them at this step in the process as well. Use a sharp knife to divide tubers, making sure each piece has at least one eye.
The eyes of dahlias are the set of cells that produce the next season’s plants and blooms. They almost look like pimples. If you can’t identify them in the fall, wait until the spring to divide your tubers as they may be more visible by then.
Step 4: Dry them off.
If possible, dry your dahlia tubers for several weeks before putting them away in storage for the winter. This helps to cure them and to prevent rot during storage.
Choose a location — either indoors or out — that won’t dip below freezing and, has good air circulation and indirect sunlight. After your tubers have dried, cut back the rest of the dahlia stem with pruners or a sharp knife.
Step 5: Store for winter.
The key to successfully storing dahlia tubers for the winter is making sure they stay dry, have good air circulation and are in a cool, dark spot.
You can store the tubers in a variety of containers — milk crates, plastic bins, paper bags and cardboard boxes all do the trick. Just make sure there is space left between each tuber and there is some air circulation.
Place the tubers in a cool, dark space that won’t freeze. For many, this could be an unheated basement, attic, closet or utility room.
Once spring arrives, ground temperatures have warmed and there is no more chance of frost in your area, you can bring your beloved tubers out of storage and replant them in your garden to enjoy again.