Digging & Storing Dahlia Tubers for Winter

Enjoy Your Beautiful Dahlias Year After Year

Dahlias are not winter-hardy in Ontario, but with proper care, their tubers can be saved and replanted each spring. Digging and storing your tubers at the end of the growing season is a rewarding way to enjoy your favourite dahlia varieties for years to come.

Step 1 — Wait Until the First Frost

After the first fall frost has blackened the foliage, prepare to lift your dahlia tubers. Allow them to remain in the ground briefly if conditions permit, but always dig them before the soil freezes.

Step 2 — Carefully Dig Up Your Tubers

Cut the stems back to approximately 4–6 inches above the ground.

Using a garden fork or shovel, loosen the soil about 12 inches away from the main stem. Carefully lift the entire tuber clump, taking care not to damage the delicate tuber necks.

Gently remove excess soil and label each clump with its variety name.

Step 3 — Clean and Dry

Remove any damaged or rotting tubers and gently brush or wash away excess soil.

Allow the clumps to dry in a cool, sheltered, well-ventilated location before placing them into winter storage. Avoid direct sunlight and freezing temperatures.

You can store the tubers as intact clumps and divide them into individual tubers the following spring.

Step 4 — Store in a Cool, Frost-Free Location

Place your tubers in boxes or containers with a suitable storage material, such as coarse vermiculite or wood shavings, to help prevent excessive moisture loss.

For best results:

• Temperature: Maintain approximately 4–7°C.
• Location: Choose a cool, dark, frost-free space.
• Moisture: Keep tubers from becoming excessively dry or wet.
• Protection: Never allow tubers to freeze.

A cool basement or temperature-controlled storage area is ideal.

Step 5 — Check Throughout Winter

Inspect your stored tubers approximately once a month.

Remove any showing signs of rot and watch for excessive shrivelling, which can indicate overly dry storage conditions. Adjust moisture or ventilation as needed.

When spring arrives, inspect your tubers for healthy growth eyes, divide clumps if desired and prepare them for planting after the danger of frost has passed.

A Little Care for Another Season of Beautiful Flowers

With careful digging, proper winter storage and a little attention throughout the colder months, your dahlia tubers can reward you with another season of spectacular blooms.