How to Store Dahlia Tubers Over Winter
There are a lot of ways to store dahlia tubers, and that can make the process seem more complicated than it really is. The goal is fairly simple: keep your tubers cool, dormant, and protected from both rot and excessive drying until spring.
At Ribier Gardens, I divide most of our clumps in fall because of space. With the number of dahlias we grow, storing whole clumps simply isn’t practical. But for a home gardener, waiting until spring has real advantages. You’re not rushing to get everything divided in fall, and as the clumps warm in spring the eyes often become easier to see.
If I were storing clumps whole until spring, I would leave them unwashed. Dirt helps protect them from drying out, and there is no reason to wash them until you are ready to divide.
For the clumps I divide in fall, I wash them first so I can clearly see the crown and eyes. I try to wash clumps within about 10 days of digging and divide them within a week after washing.
The biggest thing I have learned is this: do not let your tubers dry out while you are waiting to process them.
Freshly dug clumps stay in crates on top of cardboard boxes and under tarps until I can get to them. I never set them directly on concrete. Desiccation can do a lot of damage long before the tubers ever make it into winter storage.
After dividing, I let the cut surfaces dry just enough to callus. I put the tubers into their storage boxes and leave the lids open for about 12–24 hours. I want the cuts dry, but I do not want the tubers themselves drying out.
Temperature Matters
I store our tubers in a walk-in cooler with a small heater set to about 43°F.
You do not need a cooler. A basement, garage, cellar, refrigerator, or other protected space can work. What matters most is keeping the temperature cool and relatively stable.
Too cold and the tubers can freeze. Too warm and they may begin breaking dormancy too early. Warmth also encourages mold.
For most home growers, somewhere in the neighborhood of 40–50°F is a reasonable target.
Humidity Matters Too
Because our climate is dry, I store divided tubers in plastic shoeboxes. The plastic helps hold humidity around the tubers and keeps them from slowly drying out over winter.
In a very humid climate, I might choose something more breathable.
That is why I do not think there is one perfect storage container. The container should make up for what your storage space is lacking.
I aim for roughly 70–75% humidity. Again, the number matters less than what the tubers are telling you. If they are shriveling, they are too dry. If you are seeing condensation, mold, or soft rot, they are probably too wet.
What Should You Pack Them In?
I have had the best luck with pine shavings.
They are lightweight, inexpensive, and they work well in our conditions.
That said, I am becoming less convinced that a storage medium is always necessary.
Last winter, I stored some tubers in plastic boxes with no medium at all, and they did well. I am expanding that experiment this winter.
If it continues to work, the advantages are pretty obvious: less money, less space, less mess, and a lot less time spent packing tubers.
For now, pine shavings remain my most reliable method. But I am very interested in seeing whether the storage environment itself matters more than what the tubers are packed in.
Check Them During Winter
Do not pack your tubers away and forget about them until spring.
I check mine periodically for shriveling, rot, mold, or early sprouting.
A little wrinkling does not necessarily mean a tuber is lost. But if tubers are becoming very lightweight or badly shriveled, the storage area is too dry.
If they are soft, wet, or repeatedly molding, you probably have too much moisture or not enough airflow.
The sweet spot is somewhere in between.
The Ribier Gardens Method
For us, the process is simple:
Dig. Protect the clumps from drying. Wash. Divide. Let fresh cuts dry briefly. Pack in plastic shoeboxes with pine shavings. Store around 43°F. Keep humidity moderate. Check them through winter.
It is not the only way to store dahlias, but it is the method that has worked best for us.
And if you prefer to leave your clumps whole until spring? That can be a very good choice too.
The real goal is not to copy someone else’s system exactly. It is to keep your tubers cool, dormant, and healthy until planting season returns.
For more growing information, see our Complete Guide to Growing Dahlias and When to Plant Dahlia Tubers.
Shop Dahlia Tubers
How to Store Dahlia Tubers
How to Store Dahlia Tubers Over Winter
There are a lot of ways to store dahlia tubers, and that can make the process seem more complicated than it really is. The goal is fairly simple: keep your tubers cool, dormant, and protected from both rot and excessive drying until spring.
At Ribier Gardens, I divide most of our clumps in fall because of space. With the number of dahlias we grow, storing whole clumps simply isn’t practical. But for a home gardener, waiting until spring has real advantages. You’re not rushing to get everything divided in fall, and as the clumps warm in spring the eyes often become easier to see.
If I were storing clumps whole until spring, I would leave them unwashed. Dirt helps protect them from drying out, and there is no reason to wash them until you are ready to divide.
For the clumps I divide in fall, I wash them first so I can clearly see the crown and eyes. I try to wash clumps within about 10 days of digging and divide them within a week after washing.
The biggest thing I have learned is this: do not let your tubers dry out while you are waiting to process them.
Freshly dug clumps stay in crates on top of cardboard boxes and under tarps until I can get to them. I never set them directly on concrete. Desiccation can do a lot of damage long before the tubers ever make it into winter storage.
After dividing, I let the cut surfaces dry just enough to callus. I put the tubers into their storage boxes and leave the lids open for about 12–24 hours. I want the cuts dry, but I do not want the tubers themselves drying out.
Temperature Matters
I store our tubers in a walk-in cooler with a small heater set to about 43°F.
You do not need a cooler. A basement, garage, cellar, refrigerator, or other protected space can work. What matters most is keeping the temperature cool and relatively stable.
Too cold and the tubers can freeze. Too warm and they may begin breaking dormancy too early. Warmth also encourages mold.
For most home growers, somewhere in the neighborhood of 40–50°F is a reasonable target.
Humidity Matters Too
Because our climate is dry, I store divided tubers in plastic shoeboxes. The plastic helps hold humidity around the tubers and keeps them from slowly drying out over winter.
In a very humid climate, I might choose something more breathable.
That is why I do not think there is one perfect storage container. The container should make up for what your storage space is lacking.
I aim for roughly 70–75% humidity. Again, the number matters less than what the tubers are telling you. If they are shriveling, they are too dry. If you are seeing condensation, mold, or soft rot, they are probably too wet.
What Should You Pack Them In?
I have had the best luck with pine shavings.
They are lightweight, inexpensive, and they work well in our conditions.
That said, I am becoming less convinced that a storage medium is always necessary.
Last winter, I stored some tubers in plastic boxes with no medium at all, and they did well. I am expanding that experiment this winter.
If it continues to work, the advantages are pretty obvious: less money, less space, less mess, and a lot less time spent packing tubers.
For now, pine shavings remain my most reliable method. But I am very interested in seeing whether the storage environment itself matters more than what the tubers are packed in.
Check Them During Winter
Do not pack your tubers away and forget about them until spring.
I check mine periodically for shriveling, rot, mold, or early sprouting.
A little wrinkling does not necessarily mean a tuber is lost. But if tubers are becoming very lightweight or badly shriveled, the storage area is too dry.
If they are soft, wet, or repeatedly molding, you probably have too much moisture or not enough airflow.
The sweet spot is somewhere in between.
The Ribier Gardens Method
For us, the process is simple:
Dig. Protect the clumps from drying. Wash. Divide. Let fresh cuts dry briefly. Pack in plastic shoeboxes with pine shavings. Store around 43°F. Keep humidity moderate. Check them through winter.
It is not the only way to store dahlias, but it is the method that has worked best for us.
And if you prefer to leave your clumps whole until spring? That can be a very good choice too.
The real goal is not to copy someone else’s system exactly. It is to keep your tubers cool, dormant, and healthy until planting season returns.
For more growing information, see our Complete Guide to Growing Dahlias and When to Plant Dahlia Tubers.
Shop Dahlia Tubers