Table of Contents
- Introduction
- Knowing When to Dig Your Cannas
- Step-by-Step Digging Process
- Cleaning and Curing Your Rhizomes
- Dividing Canna Rhizomes for More Plants
- Choosing the Best Storage Medium
- Optimal Storage Conditions
- Managing Cannas in Containers
- Winter Maintenance and Troubleshooting
- Waking Up Cannas in Spring
- Conclusion
- FAQ
Introduction
There is nothing quite like the tropical flair that Assorted Cannas bring to a summer garden. Their bold, architectural foliage and vibrant, nectar-rich flowers create a vacation-like atmosphere right in your backyard. As the season winds down, many gardeners look forward to preserving these beautiful plants so they can enjoy them again next year. At Longfield Gardens, we want to help you make the most of your garden by ensuring your favorite plants return season after season.
Learning how to store canna lily bulbs—which are technically called rhizomes—is a simple and rewarding process. This guide is designed for home gardeners who want a reliable way to keep their cannas safe through the winter months. For a broader overview, see All About Cannas. We will cover everything from the right time to dig to the best ways to pack them for their winter nap.
By following a few basic steps, you can protect your investment and look forward to even bigger, better blooms next summer. Storing your cannas is one of those easy wins that makes gardening feel both sustainable and deeply satisfying.
Knowing When to Dig Your Cannas
Timing is everything when it comes to overwintering tender plants. For canna lilies, the best signal comes from nature itself. In most regions of the United States, you should wait until the first frost of autumn to begin the process. A light frost will turn the leaves brown or black, which is a clear sign that the plant has finished its work for the year.
The reason we wait for this frost is simple: it tells the plant to go dormant. As the foliage dies back, the energy from the leaves moves down into the rhizome, which is the thick, underground stem where the plant stores food. This extra energy helps the canna survive the winter and provides the fuel it needs to sprout again in the spring.
If you live in a climate where frost comes very late or not at all, you can still dig your cannas once the foliage begins to yellow and look tired in late autumn. However, for those in cooler zones, the frost is a helpful "reset button" for the plant. We recommend digging the rhizomes before the ground actually freezes solid, as extreme cold reaching into the soil can damage the delicate plant tissues.
Understanding Your Zone
Whether you need to dig your cannas at all depends largely on where you live. Canna lilies are tropical plants that are generally hardy in zones 8 through 11, so the USDA Hardiness Zone Map is a helpful reference.
If you are in zone 7, you are in a "swing" zone. Many gardeners here find that a thick layer of mulch—about six to eight inches of straw, leaves, or wood chips—is enough to protect the cannas in the ground. However, if a particularly cold winter is predicted, digging them is the safer choice. For those in zones 6 and colder, digging and storing indoors is essential for the plant's survival.
Key Takeaway: Wait for the first frost to blacken the leaves before digging. This ensures the plant has stored enough energy for its winter dormancy.
Step-by-Step Digging Process
Once the first frost has arrived, it is time to get your hands in the dirt. Digging canna rhizomes is not difficult, but it does require a bit of care to avoid "nicking" or slicing the plant. For a more detailed walkthrough, see How to Remove Canna Lily Bulbs. A damaged rhizome is more prone to rot during storage, so a gentle touch is best.
Start by cutting the foliage back. Use a clean pair of garden shears or a sharp knife to cut the stems down to about two to four inches above the soil line. Removing the bulky leaves makes it much easier to see what you are doing and handle the clumps.
Next, you will want to give the plant plenty of space. Do not aim your shovel directly at the base of the stems. Instead, start about a foot away from the center of the plant. Use a garden spade or a sturdy digging fork to loosen the soil in a circle all the way around the clump.
Lifting the Clump
After you have loosened the soil, gently pry the clump upward. Cannas grow horizontally, so the rhizomes can spread out further than you might expect. If you feel resistance, move your shovel a bit further back and loosen the soil again.
Once the clump is free, lift it out of the ground. You will likely see a large, heavy mass of rhizomes and soil. Shake the clump gently to remove the biggest chunks of dirt. At this stage, you don't need to get them perfectly clean, but removing the heavy soil makes them much easier to move to your workspace.
- Cut stems to 2–4 inches.
- Dig a wide circle around the plant.
- Lift carefully to avoid bruising the rhizomes.
- Shake off loose soil.
Cleaning and Curing Your Rhizomes
After digging, the next step is cleaning. While some gardeners prefer to leave a little soil on the rhizomes, most find that a cleaner plant is easier to monitor for health during the winter. You can use your hands to brush away the remaining soil, or if your soil is heavy clay, a gentle spray from a garden hose can help.
If you choose to wash your rhizomes, it is very important that you let them dry completely before packing them away. Storing wet rhizomes is a recipe for mold and rot. For another overview, see How to Keep Canna Lily Bulbs Over Winter. This brings us to the "curing" phase.
The Importance of Curing
Curing is simply the process of letting the rhizomes air dry in a protected spot. This helps the "skin" of the rhizome toughen up slightly and ensures that any excess moisture on the surface has evaporated.
Place your cleaned rhizomes in a well-ventilated area that is out of direct sunlight and protected from rain. A garage, a covered porch, or a shed works well, provided the temperature stays above freezing. Let them sit for a few days—up to a week is usually sufficient. You want the outer surface to feel dry to the touch, and any remaining soil should be dry enough to crumble away easily.
Dividing Canna Rhizomes for More Plants
One of the most exciting things about growing cannas is how much they multiply. A single rhizome planted in the spring can turn into a large clump by autumn. How to Divide Canna Lily Bulbs is a simple way to expand your garden for free or share plants with friends and neighbors.
Dividing your cannas allows you to expand your garden for free or share plants with friends and neighbors. You can divide them either in the fall before you store them or in the spring before you plant them. Many gardeners find that spring division is slightly better because you can clearly see the "eyes"—the small bumps or sprouts where new growth will emerge.
How to Divide
If you choose to divide in the fall, look for natural weak points in the clump where the rhizomes are joined. You can often snap them apart by hand, or you can use a clean, sharp knife. Each division should have at least one to three healthy eyes. These eyes look like small, pointed nubs on the surface of the rhizome.
If a rhizome feels mushy or looks shriveled and dry, it is best to discard it. You only want to store the firm, healthy pieces that have the best chance of thriving next season.
Key Takeaway: Each divided piece must have at least one "eye" to grow into a new plant next year. Only keep firm, healthy rhizomes.
Choosing the Best Storage Medium
Once your rhizomes are clean, dry, and perhaps divided, they need a cozy place to spend the winter. You cannot simply leave them exposed to the air in a box, as they will dry out too much and die. On the other hand, you can't seal them in an airtight container, or they will rot from their own respiration.
The goal is to find a middle ground: a storage medium that holds a tiny bit of moisture but also allows the plant to breathe. We have found several materials that work exceptionally well for this purpose.
Peat Moss or Coco Coir
Peat moss is a classic choice for storing bulbs and rhizomes. It is naturally sterile and does a great job of regulating moisture. If you find your peat moss is bone-dry, you can mist it very lightly with water before packing the rhizomes. It should feel barely damp, like a sponge that has been wrung out thoroughly. Coco coir is a great, sustainable alternative that works the same way.
Wood Shavings or Sawdust
Pine shavings—the kind often sold as bedding for small animals—are another excellent option. They provide great airflow and are very easy to handle. Sawdust works too, but make sure it comes from untreated wood. These materials are particularly good if you live in a humid climate where rot is a bigger concern than drying out.
Newspaper or Cardboard
If you don't have peat or shavings on hand, shredded newspaper or even wrapping the rhizomes individually in sheets of newspaper can work. The paper provides a layer of insulation and helps absorb any excess moisture that might lead to mold.
Storage Containers
When it comes to the container itself, cardboard boxes, plastic bins with holes drilled in the sides, or breathable mesh bags are all good choices. If you use a plastic bin, do not put the lid on tightly. A bit of airflow is your best friend when learning how to store canna lily bulbs.
Optimal Storage Conditions
Now that your cannas are packed, they need a home for the winter. The location you choose will determine whether they stay dormant or start to grow (or worse, freeze).
The ideal temperature for storing canna rhizomes is between 45°F and 55°F. This is cool enough to keep the plant in a state of deep sleep but warm enough to prevent tissue damage from freezing.
Where to Store
- Unheated Basements: These often provide the perfect, consistent temperature.
- Root Cellars: These are traditionally designed for this exact purpose and offer excellent humidity and temperature control.
- Crawl Spaces: If your home has a crawl space that stays above freezing, it can be a great hidden storage spot.
- Cool Closets: In warmer zones, an interior closet in a garage or an unheated part of the house may stay within the right temperature range.
Avoid storing your cannas in a location that gets too warm, such as near a furnace or a water heater. If the temperature stays above 60°F, the rhizomes may think it is spring and start to sprout prematurely, which wastes the energy they need for the actual growing season. Similarly, avoid uninsulated garages in very cold climates, as the temperature can easily drop below freezing during a cold snap.
Managing Cannas in Containers
Many gardeners choose to grow cannas in large pots on patios or decks. If this is your situation, Summer Blooming Bulbs for Containers is a good place to browse.
One option is to treat the container-grown canna just like a garden-grown one: dig it up, clean it, and store the rhizomes in a medium. However, many people find it easier to simply leave the rhizomes in the pot.
Storing the Entire Pot
After the first frost kills the foliage, cut the stems back to the soil level as usual. Instead of digging the rhizomes out, simply move the entire pot into a frost-free area like a basement or a cool garage. For more tips on container growing, see How to Grow Summer Bulbs in Containers.
When storing in the pot, you do not need to water the plant. The soil should be allowed to dry out almost completely. The dry soil acts as the storage medium, protecting the rhizomes from the air. In the spring, you can bring the pot back out, give it a good soak, and watch the new shoots emerge. This is a very convenient method if you have the space to store larger containers.
What to Do Next:
- Identify your storage location (45–55°F is best).
- Select a breathable container like a cardboard box.
- Choose your packing material (peat moss or shavings).
- Place the packed box in a dark, cool spot.
Winter Maintenance and Troubleshooting
Storing your cannas is not a "set it and forget it" task. To ensure the highest success rate, we recommend checking on your stored rhizomes about once a month. This small effort can save your entire collection if something starts to go wrong.
Checking for Moisture
When you check your rhizomes, feel the storage medium. If it feels completely dry and the rhizomes are starting to look shriveled or wrinkled, they are losing too much moisture. Use a spray bottle to lightly mist the packing material. You don't want it wet—just slightly "not-dry." This small amount of humidity will help the rhizomes stay plump.
Watching for Rot
On the flip side, if you see any fuzzy mold or if a rhizome feels soft and mushy, it is suffering from too much moisture. Rot can spread quickly from one rhizome to another, so it is important to act fast. Remove any affected rhizomes and throw them away. If the storage medium feels damp, replace it with fresh, dry material and ensure your container has better ventilation.
At Longfield Gardens, we believe that observing your plants is the best way to learn what they need. Every home has a slightly different microclimate, so your "monthly check-in" will help you dial in the perfect balance for your specific environment.
Waking Up Cannas in Spring
When the days begin to lengthen and the threat of hard frost passes, it is time to start thinking about spring. You can start your canna lilies indoors about 4 to 6 weeks before the last expected frost date to give them a head start on the season. When you're ready to shop, browse Shop All Spring Planted Bulbs.
Take the rhizomes out of their storage boxes and inspect them one last time. They should feel firm and heavy. If you didn't divide them in the fall, now is the perfect time to do so. Plant them in pots with high-quality potting soil, keeping the "eyes" pointing upward. Place them in a warm, sunny window or under grow lights.
By the time the soil outside has warmed up to about 60°F, your cannas will already have a strong root system and perhaps several inches of green growth. This "head start" method is particularly useful for gardeners in northern states with shorter growing seasons, as it ensures you get flowers much earlier in the summer.
Moving Outdoors
When you are ready to move them to the garden, remember the rule of "right plant, right place." Cannas love full sun and rich, well-draining soil. They are heavy feeders, so adding a bit of compost or a balanced fertilizer at planting time will help them reach their full potential.
The transition from the cozy indoors to the bright garden should be gradual. Spend a few days "hardening off" your plants by placing them in a sheltered, shady spot during the day and bringing them in at night, slowly increasing their exposure to sun and wind.
Conclusion
Mastering how to store canna lily bulbs is a simple skill that transforms your gardening experience. Instead of treating these tropical beauties as annuals, you can keep them for years, watching your collection grow as the rhizomes multiply. The process—from waiting for that first frost to checking on them in the basement—is a natural part of the gardener’s rhythm.
At Longfield Gardens, we want you to feel confident in every step of your gardening journey. While weather and storage conditions can vary, the basics remain the same: keep them cool, keep them slightly damp but not wet, and protect them from the bite of a deep freeze.
- Wait for frost to signal dormancy before digging.
- Cure the rhizomes to prevent rot.
- Store in a cool, breathable environment.
- Check monthly to ensure the perfect moisture balance.
Storing your own canna rhizomes is a rewarding way to build a spectacular garden over time. With just a little bit of care, those bold, tropical colors will be ready to light up your backyard again next summer.
We invite you to explore the different colors and heights available, including Tall Cannas, to find the perfect match for your landscape.
Whether you are a beginner or a seasoned pro, the joy of seeing those first green spikes emerge in the spring never fades. For medium-size options, browse Medium Cannas.
For more compact plants, browse Short Cannas. Happy gardening!
FAQ
Should I wash the dirt off canna rhizomes before storing them?
While you don't have to get them perfectly clean, rinsing or brushing off excess soil makes it easier to inspect the rhizomes for rot or damage. If you do wash them with a hose, it is essential to let them air dry completely for several days before packing them away to prevent mold.
What happens if I forget to dig my cannas before the ground freezes?
If only the surface of the soil has a light crust of frost, the rhizomes are likely still fine. However, if the ground freezes several inches deep, the water inside the rhizomes can turn to ice, bursting the plant's cells and causing them to turn to mush. If you've had a deep freeze, check the rhizomes; if they are firm, they may still be viable.
Can I store canna bulbs in the refrigerator?
A refrigerator is generally too cold and lacks the proper humidity for canna storage. Most refrigerators are kept around 35-38°F, which can damage tropical rhizomes over a long period. A cool basement or crawl space between 45-55°F is much more suitable for their needs.
How do I know if my stored canna rhizomes are still good in the spring?
Healthy rhizomes should feel firm and relatively heavy for their size, similar to a fresh ginger root. If a rhizome feels light, hollow, or shriveled, it has dried out too much. If it is soft, mushy, or has a sour smell, it has rotted and should be discarded before planting.