Storing Canna Bulbs for the Winter

Table of Contents

1. Introduction
2. Understanding the Canna Life Cycle
3. When to Begin the Storage Process
4. Preparing the Plants for Digging
5. The Proper Technique for Digging Cannas
6. Cleaning and Inspecting Your Rhizomes
7. The Importance of Curing
8. Selecting the Best Storage Containers
9. Choosing a Packing Medium
10. The Ideal Storage Environment
11. Mid-Winter Maintenance and Checks
12. Special Considerations for Potted Cannas
13. Troubleshooting Common Storage Issues
14. Preparing for Spring Replanting
15. Why Quality Matters
16. Conclusion
17. FAQ

Introduction

There is a special kind of magic in watching a canna lily transform a summer garden into a lush, tropical paradise. Their oversized leaves and vibrant, torch-like flowers bring an architectural beauty to the landscape that few other plants can match. At Longfield Gardens, we believe that the joy of growing these stunning plants shouldn't end when the first autumn breeze arrives, and our Spring-Planted Summer-Blooming Bulbs collection makes it easy to plan ahead. By taking a few simple steps now, you can preserve your favorite varieties and enjoy their spectacular display year after year.

This guide is designed for any gardener who wants to save their canna rhizomes—often called bulbs—from the winter cold. We will walk you through the timing, the digging process, and the best ways to keep your plants healthy while they rest indoors. Storing canna bulbs for the winter is a rewarding practice that saves money and allows you to build a larger, more impressive garden over time, and if you want to grow a standout variety, Canna Tall Pretoria is available from Longfield Gardens. With a little care, you can ensure these tropical beauties return to your garden even stronger next season.

Understanding the Canna Life Cycle

Cannas are tropical and subtropical plants that thrive in heat and humidity. In warmer climates, such as USDA zones 8 through 11, they can often stay in the ground year-round. However, for most gardeners in the United States, winter temperatures drop low enough to freeze the soil and destroy the tender underground stems, known as rhizomes. If you'd like to browse more options, the Tall Cannas collection includes several bold selections.

The rhizome is a thick, fleshy part of the plant that grows horizontally beneath the soil surface. It serves as a storage tank for energy, holding all the nutrients the plant needs to sprout again in the spring. Because cannas are not frost-hardy, they rely on us to move them to a protected spot before the deep freeze sets in.

Think of winter storage as a nap for your plants. They aren't dead; they are simply dormant, waiting for the warmth of spring to wake them up. Successfully overwintering your cannas depends on keeping these rhizomes in a state where they are neither too wet (which causes rot) nor too dry (which causes them to shrivel and die).

When to Begin the Storage Process

Timing is everything when it comes to storing canna bulbs for the winter. If you dig them up too early, the rhizomes may not have stored enough energy to last through the dormant season. If you wait too long, a hard freeze might penetrate the soil and damage the living tissue.

The most reliable signal to start is the weather. You want to wait until the first light frost hits your area. You will know it has happened because the lush green or burgundy foliage of your cannas will suddenly turn black or dark brown. While this might look disappointing, it is actually a helpful sign. This frost tells the plant to stop sending energy to the leaves and start tucking it away in the rhizomes.

It is perfectly fine to let the plants sit in the ground for a few days after this first frost. In fact, many gardeners wait for the foliage to completely wither. However, you should aim to have them out of the ground before the soil itself begins to freeze solid. A light frost kills the leaves, but a deep freeze kills the plant. Keeping an eye on your local weather forecast during late September and October will help you pick the perfect weekend for the task.

What to do next:

• Monitor your local weather for the first "killing frost."
• Observe the foliage for color changes from green to black or brown.
• Gather your tools, including a garden fork, sturdy gloves, and pruning shears.

Preparing the Plants for Digging

Before you lift the rhizomes out of the earth, you need to clear away the top growth. This makes the job much easier and prevents you from wrestling with heavy, frost-damaged stalks. Using a sharp pair of pruning shears or a garden knife, cut the stalks back so only about 3 to 4 inches of the stem remains above the soil line.

This remaining "handle" serves two purposes. First, it helps you see exactly where the center of the plant is so you don't accidentally slice through the rhizome with your shovel. Second, it provides a convenient place to grab the plant as you lift it.

Once the tops are removed, clear away any mulch or debris from the base of the plant. If you have multiple varieties, such as a tall "Pretoria" with striped leaves and a shorter variety with dark foliage, this is the best time to label them. It is very easy to forget which plant is which once they are just brown rhizomes in a box. You can write the name directly on the stem handle with a permanent marker or attach a small plastic tag.

The Proper Technique for Digging Cannas

Digging up canna rhizomes is a straightforward process, but it requires a gentle touch. Because these rhizomes are fleshy and full of moisture, they can be easily bruised or cut. A damaged rhizome is more likely to develop mold or rot during the winter months.

We recommend using a garden fork rather than a pointed shovel. A fork allows you to loosen the soil around the plant without the high risk of slicing through the root mass. Start by inserting the fork into the soil about 12 inches away from the base of the stems. If you have large, established clumps, you may need to start even further back. Cannas can spread significantly during a single growing season.

Work your way around the entire plant, prying upward gently to loosen the root ball. You want to lift the entire mass of soil and rhizomes as one unit. Once the soil is loose, reach under the clump and lift it out of the hole. If the clump is too heavy to lift at once, you can gently use your hands or the fork to wiggle it apart into smaller sections.

After the rhizomes are out of the ground, shake them gently to remove large clods of soil. Avoid banging them against a hard surface, as this can cause "bruising." You don't need to get them perfectly clean yet; the goal is just to remove the bulk of the garden earth so they are easier to handle.

Cleaning and Inspecting Your Rhizomes

Once your cannas are out of the ground, move them to a workspace like a garage floor, a potting bench, or a tarp on the lawn. Now you can take a closer look at what you’ve harvested. Use your hands to brush away the remaining loose soil. Some gardeners prefer to wash their rhizomes with a garden hose, but this isn't strictly necessary and adds a lot of moisture that you will eventually have to dry out.

If you do choose to wash them, ensure you do it on a sunny day so they can dry quickly. A light brushing is usually enough. As you clean, look for any soft spots, signs of insect damage, or mushy areas. Healthy canna rhizomes should feel firm, similar to a fresh potato or ginger root. If you find any parts that are clearly rotting, use a clean, sharp knife to cut those sections away.

If you find that your canna clumps have grown very large, you can take this opportunity to divide them. Canna rhizomes naturally grow in segments with "eyes" (small bumps where new stems will grow). You can snap or cut them into smaller pieces, as long as each piece has at least one or two healthy eyes. Dividing your plants every year or two keeps them vigorous and prevents the clumps from becoming unmanageable.

Key Takeaway: Healthy storage starts with healthy plants. Only keep rhizomes that are firm and free of rot. Labeling each variety now saves confusion during the excitement of spring planting.

The Importance of Curing

Curing is a vital step that many beginners skip. It is the process of letting the outer skin of the rhizome dry and toughen up slightly before it goes into storage. This "toughening" acts as a natural shield against rot and disease.

To cure your cannas, place the cleaned rhizomes in a warm, dry area with good air circulation. A garage, shed, or covered porch works well, as long as the temperature stays above freezing. For a broader explanation of what helps plants handle seasonal extremes, see Know Your Growing Zone: Cold Hardiness and Heat Tolerance.

Spread them out in a single layer rather than stacking them. This ensures that air can reach every surface. Let them sit for two to three days. During this time, any remaining soil will dry into a dust that can be easily brushed off, and the cut ends of the stems will callus over. Do not leave them out for more than a few days, or the rhizomes may begin to shrivel. They should still feel heavy and firm, not light and hollow.

Selecting the Best Storage Containers

When it comes to the actual storage, you have several options for containers. The goal is to provide a home that allows for some air exchange while preventing the rhizomes from drying out completely.

• Cardboard Boxes: These are a favorite because they are breathable and easy to stack. They allow a small amount of moisture to escape so the plants don't get soggy.
• Plastic Bins: If you use plastic totes, do not snap the lid on tight. Leave the lid slightly ajar or drill several small holes in the sides to allow for ventilation. Without airflow, condensation can build up inside, leading to mold.
• Paper Bags: For smaller quantities, heavy-duty grocery bags work well. They provide excellent breathability but may need to be checked more often to ensure the contents aren't drying out.
• Wooden Crates: These offer the best ventilation, but you may need to line them with newspaper to keep the packing material from falling through the slats.

Choosing a Packing Medium

Storing canna bulbs for the winter "naked" (without any packing material) is risky because they can lose moisture too fast. Using a packing medium helps regulate the humidity around the rhizomes. At Longfield Gardens, we have found that several different materials work effectively depending on what you have on hand.

Peat Moss

Dampened peat moss is one of the most popular choices. It is slightly acidic, which can help discourage certain types of rot. It holds moisture well but also allows for air circulation. If you use peat moss, make sure it is only barely damp—if you squeeze a handful, no water should drip out.

Vermiculite or Perlite

These are lightweight, mineral-based materials often used in potting soils. They are excellent for storage because they are sterile and provide a lot of air space around the rhizomes. They don't hold as much moisture as peat moss, so they are a good choice if your storage area tends to be a bit humid.

Wood Shavings

Commonly sold as pet bedding (make sure to use cedar or pine), wood shavings are a clean and easy option. They are very breathable and provide a good cushion for the rhizomes. Like vermiculite, they are relatively dry, so you may need to check your cannas more frequently to ensure they aren't shriveling.

Newspaper

If you are looking for a budget-friendly option, shredded or bundled newspaper works surprisingly well. You can wrap each individual rhizome in a sheet of newspaper and then tuck them into a box. The paper absorbs excess moisture but also prevents the rhizomes from touching one another, which stops the spread of rot if one happens to go bad.

What to do next:

• Choose a container that fits your storage space.
• Select a packing medium like peat moss or wood shavings.
• Layer your rhizomes so they are not touching each other directly.

The Ideal Storage Environment

Once your cannas are packed, you need to find the right place for them to spend the winter. The ideal environment is cool, dark, and dry.

The perfect temperature range is between 40°F and 50°F. If the area is too warm (above 60°F), the cannas may think spring has arrived and try to sprout prematurely. If the area is too cold (below 35°F), you risk the rhizomes freezing and dying. If you need to compare your shipping timing or seasonal planning, Shipping Information explains how Longfield Gardens schedules orders by zone.

Common storage locations include:

• Unheated Basements: Most basements stay within the ideal temperature range throughout the winter.
• Crawlspaces: These are often cool and dark, though they can sometimes be a bit damp, so monitor for mold.
• Attached Garages: If your garage is insulated and stays above freezing, it can be a great spot. However, keep the boxes off the cold concrete floor by placing them on a shelf or a wooden pallet.
• Closets in Cool Parts of the House: If you don't have a basement or garage, a closet on an exterior wall in a room you don't heat heavily may stay cool enough.

Avoid storing your cannas near large appliances like water heaters or furnaces, which can create pockets of dry, hot air. Also, keep them away from stored fruits like apples or pears, as these release ethylene gas which can interfere with the dormancy of the bulbs.

Mid-Winter Maintenance and Checks

One of the most important parts of storing canna bulbs for the winter is the monthly check-up. It is easy to "set it and forget it," but a quick five-minute inspection once a month can save your entire collection.

Mark your calendar for the first of every month. Open your boxes and take a look at a few of the rhizomes. You are looking for two things: rot and dehydration.

If you find a rhizome that feels mushy, slimy, or smells bad, remove it immediately. Rot can spread quickly from one plant to another if they are in close contact. If only a small tip is soft, you can cut it off, let it dry for a day, and put it back, but usually, it's safer to discard the affected piece.

On the other hand, if the rhizomes feel very light and look wrinkled or shriveled, they are losing too much moisture. To fix this, use a spray bottle to lightly mist the packing medium with water. You don't want it to be "wet"—just a tiny bit of humidity to stop the drying process.

Special Considerations for Potted Cannas

Many gardeners choose to grow cannas in large decorative pots to anchor their patio or deck. If you have potted cannas, you have a shortcut available to you. Instead of digging the rhizomes out of the soil, you can simply move the entire pot into storage.

After the first frost kills the foliage, cut the stalks back as you would for garden-grown plants. Allow the soil in the pot to dry out almost completely. Then, move the entire container into your cool, dark storage area. The dry soil in the pot acts as the perfect packing medium, insulating the rhizomes and keeping them at a steady temperature.

In the spring, about six weeks before the last frost, you can bring the pot back into the light, give it a good drink of water, and watch the new shoots emerge. This is an excellent method for those with limited time or space.

Troubleshooting Common Storage Issues

Even with the best care, things can sometimes go sideways. The key is not to worry—gardening is a learning process, and most issues are easily fixed if caught early.

If you notice a white, fuzzy mold growing on the surface of your rhizomes, it usually means the air is too stagnant or the packing medium is too damp. Increase the ventilation by opening the box more or moving it to a spot with better air movement. You can gently wipe the mold off with a dry cloth.

If your cannas start to sprout long, pale white stems in February or March, your storage area is likely too warm. Move the boxes to a cooler spot to slow them down. If it is still months away from planting time, you may need to pot them up in some soil and keep them near a sunny window until the weather warms up outside.

Lastly, be mindful of uninvited guests. Mice and other small rodents sometimes find canna rhizomes to be a tasty winter snack. If you have a rodent problem in your storage area, consider using plastic bins with ventilation holes or placing wire mesh over your boxes to protect your plants.

Preparing for Spring Replanting

As winter begins to fade, you will notice the "eyes" on your canna rhizomes beginning to swell or turn a lighter shade of pink or green. This is an exciting sign that they are ready to grow!

While this guide focuses on storage, it's helpful to know that you don't have to wait until the last frost to start your cannas. Many gardeners "wake them up" indoors by planting them in pots about 4 to 6 weeks before the average last frost date. This gives you a head start on the season and results in much earlier blooms.

When you are ready to move them back outside, remember the most important rule of canna care: they love heat. Do not rush them into cold, wet spring soil. Wait until the soil temperature has reached at least 60°F and all danger of frost has passed. This patience will be rewarded with faster growth and a more successful transition to the garden.

Why Quality Matters

When you start with high-quality plants, the overwintering process is much more successful. At Longfield Gardens, we work with trusted growers to ensure the rhizomes we ship to you are healthy, vigorous, and true to variety. We maintain a trial garden where we evaluate plant performance, so we know exactly what it takes for these plants to thrive in your backyard.

We stand behind our plants with a 100% Quality Guarantee. We want your gardening experience to be positive and stress-free. If your items arrive with any damage or quality issues, we encourage you to contact us promptly after delivery so we can make it right. Our goal is to help you create the most beautiful garden possible, and that starts with premium bulbs and perennials that are ready to perform.

Conclusion

Storing canna bulbs for the winter is one of the most practical and satisfying skills a gardener can learn. It allows you to preserve the specific colors and heights that work perfectly in your landscape, while also giving you the chance to expand your garden for free by dividing healthy clumps. By following the simple steps of digging after the frost, curing the rhizomes, and providing a cool, dark resting place, you can ensure a tropical encore year after year.

Remember that gardening is a partnership with nature. Some years the weather might be perfectly cooperative, and other years it might throw a few curveballs. By staying observant and checking your stored plants occasionally, you will find that overwintering is an easy win for your garden.

Final Takeaways for Success:

• Dig rhizomes after the first light frost kills the foliage.
• Cure the rhizomes in a dry, protected area for 2–3 days.
• Pack in a breathable container with barely damp peat moss or wood shavings.
• Store in a cool (40–50°F), dark location and check monthly.

We hope this guide makes you feel confident and excited about keeping your cannas for next season. When you're ready to add new colors or textures to your collection, we invite you to explore our selection at Longfield Gardens and browse the Spring-Planted Bulbs By Color. We are here to support your gardening journey every step of the way, providing the quality plants and practical advice you need to grow a more beautiful world right at home.

FAQ

Do I have to dig up my canna bulbs every year?

This depends entirely on your USDA hardiness zone. If you live in Zone 8 or warmer, you can usually leave your cannas in the ground year-round, although adding a thick layer of mulch in the fall is a good safety measure. In Zone 7 and colder, the ground freezes deep enough to kill the rhizomes, so digging and storing them indoors is necessary for the plants to survive.

What should I do if my stored canna rhizomes look shriveled?

Shriveling is a sign that the rhizomes are losing too much moisture. If they still feel somewhat firm and haven't become completely hollow or brittle, they can usually be saved. Lightly mist the packing medium (like peat moss or wood shavings) with a spray bottle of water to increase the humidity in the box. This will help the rhizomes stay hydrated until it is time to plant them in the spring.

Can I store canna bulbs in the refrigerator?

While a refrigerator provides a cool and dark environment, it is generally not recommended for canna storage. Refrigerators are often too cold (usually set below 40°F) and the air is extremely dry, which can cause the rhizomes to shrivel quickly. Additionally, gasses released by ripening produce in the fridge can harm the dormant plants. A cool basement or insulated garage is a much better choice.

Should I cut the roots off the canna rhizomes before storing them?

When you dig up your cannas, you will see long, thin roots hanging off the thick rhizomes. You can trim these back to about an inch or two with clean shears to make the clumps easier to pack. However, you don't need to remove them entirely. The most important part is to avoid cutting into the thick, fleshy rhizome itself, as those wounds are where rot is most likely to start.

Do I need to check my stored cannas during winter?

Yes. A quick monthly check is one of the best ways to prevent problems. If you want more general storage and care answers, the FAQs - General Bulbs and Plants page is a useful reference.