How to Properly Dig and Store Dahlia Tubers Over Winter

Dahlias are a favorite in my garden, offering stunning blooms from summer until the first frost. But if you want to enjoy these beautiful flowers year after year, you’ll need to dig up and store your dahlia tubers properly for the winter. This process helps protect them from freezing temperatures and ensures they are ready to grow again in the spring. Here’s my step-by-step guide to successfully digging, preparing, and storing dahlia tubers through the colder months. 

Step 1: Knowing When to Dig Up Your Dahlias

The best time to dig up your dahlia tubers is after the first hard frost. The frost will cause the foliage to blacken and die back, signaling that it’s time to lift the tubers. Leaving them in the ground too long after frost can make them more susceptible to rot, while digging them up too early can result in underdeveloped tubers that may not store well.

Key Signs It’s Time to Dig:

  • The plant’s foliage turns brown or black from frost damage.

  • The plant has stopped actively growing.

  • Soil temperatures are consistently below 50°F but above freezing.

Step 2: Digging Up the Tubers

Digging up dahlia tubers requires a gentle touch to avoid damaging them. Follow these steps to safely lift them from the soil:

  1. Cut Back the Foliage – Using sharp pruners or garden shears, cut the stems back to about 4–6 inches above the ground. This makes handling the tubers easier.

  2. Loosen the Soil – Insert a garden fork or spade about 12 inches away from the base of the plant to avoid slicing into the tubers. Gently loosen the soil around the tuber clump.

  3. Lift the Tubers – Carefully lift the entire clump from the ground. Shake off excess soil, but do not wash them immediately as they need to dry out first.

Tip: If the ground is particularly wet or muddy, allow the tubers to sit in a dry, shaded area for a few hours before handling them further.

Step 3: Cleaning and Drying the Tubers

After digging up your dahlia tubers, they need to be cleaned and cured before storing.

  1. Remove Excess Dirt – Gently brush off any clumps of soil. I will gently rinse off the tuber clumps if I cannot brush off excess soil. Do not soak the tubers just spray them off with the hose. 

  2. Inspect for Damage – Check each tuber for signs of rot, disease, or breakage. Discard any that are mushy or moldy.

  3. Allow Tubers to Dry – Place the tubers in a well-ventilated, dry location out of direct sunlight for about 24- 48 hours. This allows the outer skin to toughen up and reduces the risk of mold during storage.

Note: If you live in a particularly humid climate, consider using a fan to promote air circulation during drying.

Step 4: Dividing the Tubers (Optional)

You can divide your dahlia tubers in the fall before storage or wait until spring before planting. If you choose to divide them in the fall:

  1. Identify the “Eyes” – Each tuber must have at least one eye (growth point) and a portion of the crown (the thick part where the tuber connects to the stem). The eyes look like small bumps and are easier to see after the tubers have dried up. 

  2. Use Sharp, Clean Tools – Sharp pruners work best for cutting the tubers apart. Always disinfect your tools before and after use on each tuber clump to prevent disease spread.  A bleach solution works great. 

  3. Discard Weak Tubers – Remove any shriveled, moldy, or rotting tubers. Only firm, healthy tubers should be stored with visible eyes. 

Step 5: Preparing for Storage

Before storing your tubers, you can take a few extra steps to help prevent rot and disease:

  • Dust with Sulfur Powder – Some gardeners lightly coat tubers with powdered sulfur to prevent fungal infections.

  • Dust with Cinnamon Powder - I personally use cinnamon on my Dahlia tubers where I've made a cut to divide the tubers. Some say it doesn't work however it has worked well for me for the last 4 years. 

  • Use a Bleach Dip (Optional) – A diluted bleach solution (1 part bleach to 9 parts water) can be used to sanitize the tubers before storage. If using this method, allow the tubers to dry completely before packing them away.

Step 6: Packing and Storing Tubers

Dahlia tubers need to be stored in a cool, dark, and well-ventilated area. Here’s how to do it:

  1. Choose a Storage Medium- Tubers can be stored in many different ways. Different options are available like, Peat Moss, Pine Shavings, Sawdust, Saran Wrap, Sand, Soil, Vermiculite. 

  2. Choose a Storage Method – My personal favorite method has been using the Saran wrap method. I take one dry tuber and roll it up into saran wrap layering and adding another tuber as I go into a roll of tubers of the same variety. This then gets wrapped up with the labels and placed into a wine fridge or regular refrigerator. Temperatures however needs to stay below 50 degrees F and moisture should be around 40%-50%. You don't want your tubers to dry out, but at the same time you do not want them to be too moist and rot and mold. If using any of the other methods mentioned above- layer each tuber variety in a box or plastic tote with the medium of your choice and ensure they are not touching each other. Keep the tubers covered or slightly open dependent on your humidity. 

  3. Label Your Tubers – If you have multiple varieties, label each tuber or container so you know what you’re planting next season! Especially if you want to trade or sell the extra tubers in the Spring. 

Step 7: Ideal Storage Conditions

Dahlia tubers need specific conditions to remain viable until spring:

  • Temperature: Keep tubers in a cool but frost-free location (ideally between 40°F and 50°F).

  • Humidity: Aim for 50% -60% humidity. Too much moisture causes rot, while too little can cause shriveling and your tubers to dry out. 

  • Airflow: Good air circulation helps prevent mold growth. Avoid stacking boxes too tightly. If using the saran wrap method open up your tubers and check on them periodically. I like to check on mine every few weeks to brush off any mold or make sure none are rotting or shriveling up. 

Good Storage Locations:

  • Unheated basements

  • Root cellars

  • Garages (if they don’t drop below freezing)

  • Insulated sheds

  • Wine Fridge/Refrigerator with temps under 50 degrees Fahrenheit.   

Step 8: Checking Tubers Throughout the Winter

Check on your tubers every few weeks to ensure they are in good condition:

  • If tubers appear shriveled – Lightly mist the storage medium with water to increase humidity. If using Saran wrap method check your humidity. 

  • If you see mold or rot – Remove affected tubers immediately and improve ventilation. A bit of mold is normal and not a reason to panic, just wipe or brush it off and dry the tuber off. If there is rot forming cut it off as much as possible or toss the affected tuber out. 

  • If sprouting occurs too early – Move tubers to a slightly cooler location to slow growth. 

Step 9: Preparing Tubers for Spring Planting

When the danger of frost has passed and soil temperatures reach about 60°F, it’s time to wake up your dahlia tubers for planting.

  1. Inspect the Tubers – Discard any that have dried out or rotted.

  2. Warm Them Up – Move tubers to a warmer area (around 65–75°F) about two to three weeks before planting to encourage sprouting. If wanting to take cuttings or wake tubers up for earlier blooms, feel free to wake them up 4-6 weeks early. However make sure to have adequate space and pots to pot up the tubers into once they start to grow. You will then need to keep grow lights on them and keep them inside or move them to an outdoor heated greenhouse. Keep this in mind if planning to start up your tubers early. 


Storing dahlia tubers properly ensures you’ll have a beautiful display of flowers year after year without having to buy the same verities each year. With a little effort in the fall, you can protect your tubers from winter damage and enjoy healthy, thriving plants in the spring. Happy Flower Gardening! 

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