How to Store Canna Lily Bulbs for the Winter

Table of Contents

1. Introduction
2. Understanding Canna Rhizomes
3. When to Dig Your Canna Lilies
4. Preparing the Plants for Harvest
5. How to Dig Canna Rhizomes Safely
6. The Curing Process
7. Dividing Canna Rhizomes
8. Choosing a Storage Medium
9. Step-by-Step Packing for Winter
10. The Ideal Storage Environment
11. Monitoring Your Rhizomes Through Winter
12. Alternative: Storing Potted Cannas
13. When to Bring Cannas Out of Storage
14. Realistic Expectations for Success
15. Conclusion
16. FAQ

Introduction

Canna lilies bring a spectacular tropical flair to any garden with their oversized leaves and brilliant, jewel-toned flowers. Whether you grow them for their sunset-colored petals or their striking variegated foliage, these plants are often the stars of the summer landscape. At Longfield Gardens, we love how cannas transform a standard backyard into an exotic retreat with very little effort during the growing season.

Because cannas are tropical plants, they thrive in the heat but are sensitive to freezing temperatures. If you live in a region with cold winters, you do not have to say goodbye to your favorite plants when the season ends. Learning how to store canna lily bulbs for the winter is a rewarding way to save your favorite varieties and enjoy even bigger, more impressive displays every single year. If you're comparing new varieties for next spring, the Tall Cannas collection is a good place to start.

This guide is designed for home gardeners who want a clear, step-by-step process for harvesting and overwintering their canna rhizomes. We will cover the best timing for digging, how to prepare the roots for their winter nap, and the ideal conditions for keeping them healthy until spring. By following these simple steps, you can ensure your cannas return with vigor when the warm weather returns. If you want a companion walkthrough, see How to Dig Up and Store Canna Lily Bulbs: A Simple Guide.

Understanding Canna Rhizomes

Before you begin the storage process, it is helpful to understand what you are actually digging up. While many people call them "bulbs," cannas actually grow from rhizomes. A rhizome is a thick, fleshy underground stem that stores energy for the plant. If you look closely at a canna rhizome, you will see small bumps or points known as "eyes." These eyes are where the new stems will sprout next year.

The goal of winter storage is to keep these rhizomes alive while they are dormant. Dormancy is essentially a deep sleep that the plant enters to survive unfavorable conditions, like the cold. During this time, the plant stops growing and waits for the soil to warm up again. Your job is to provide an environment that is cool enough to keep them asleep but warm enough to prevent freezing.

When to Dig Your Canna Lilies

Timing is one of the most important factors in successful winter storage. In most parts of the United States, canna lilies should be dug up in the late autumn. The best signal to start the process is the first light frost of the season.

A light frost will usually turn the lush green leaves to a dark brown or black color. While this might look disappointing at first, it is actually a helpful sign from nature. The frost tells the plant that the growing season is over and it is time to move its energy down into the rhizomes. Waiting for this first frost allows the rhizome to store as much fuel as possible for next year’s flowers.

If you live in a very cold climate where the ground freezes quickly, do not wait for a deep, hard freeze. While the foliage can handle a light frost, the rhizomes themselves can be damaged if the ground around them freezes solid. Aim to have your cannas out of the ground once the leaves have blackened but before the soil becomes difficult to dig.

Zone Considerations

Your local USDA hardiness zone determines whether you need to dig your cannas at all. In zones 8 through 11, canna lilies are generally hardy and can stay in the ground year-round. In these warmer areas, you can simply cut the foliage back to the ground after it yellows and perhaps add a layer of mulch for extra protection.

For gardeners in zones 3 through 7, the winter temperatures are too low for the rhizomes to survive outdoors. In these regions, digging and storing the rhizomes is necessary. If you are unsure of your zone, the Hardiness Zone Map is a quick reference. If your ground freezes several inches deep, your cannas will need an indoor spot for the winter.

Key Takeaway: The ideal time to dig canna rhizomes is shortly after the first frost has turned the foliage brown, but before the ground freezes solid.

Preparing the Plants for Harvest

Once the first frost has arrived, you can begin the harvesting process. Start by cutting the stems back. Use a clean pair of garden shears or a sharp knife to cut the stalks down to about two or three inches above the soil line. Removing the bulky foliage makes it much easier to see what you are doing and reduces the amount of space the plants take up in your workspace.

Don't worry about being too precise with this cut. The remaining few inches of stem will act as a handle while you are digging and will eventually dry up during the storage process. Once the tops are removed, you can clear away any mulch or debris from the base of the plants so you have a clear view of the soil.

Tools for the Job

You do not need specialized equipment to harvest cannas. A standard garden spade or a sturdy garden fork works best. A garden fork is often preferred because it is less likely to accidentally slice through the fleshy rhizomes. If you use a spade, just be sure to give the plant plenty of space as you begin to dig.

How to Dig Canna Rhizomes Safely

Canna rhizomes can grow quite large over a single summer. A small piece planted in May can turn into a heavy, multi-layered clump by October. Because of this, you should start digging several inches away from the base of the stems to avoid hitting the roots.

Insert your shovel or fork vertically into the soil about six to eight inches away from the center of the plant. Gently rock the tool back and forth to loosen the earth. Repeat this process all the way around the plant in a circle. Once the soil is loose, use the tool to gently pry the entire clump upward.

If the clump is very large and heavy, you may need to lift it in sections, but try to keep the main root mass intact as much as possible for now. Use your hands to brush away the large chunks of soil so you can see the structure of the rhizomes.

Cleaning the Rhizomes

Once the clumps are out of the ground, you have two options for cleaning them. You can either shake off the loose soil by hand or use a garden hose to gently wash the dirt away.

Washing the rhizomes with water makes it much easier to inspect them for pests or damage. However, if you use water, you must be extra diligent about the drying process that follows. If you choose to leave the soil on, simply remove the largest clumps and allow the rest to dry naturally. At Longfield Gardens, we find that a gentle rinse often helps gardeners see the "eyes" more clearly, which is helpful if you plan to divide them later. If you want a simple way to judge whether a rhizome is worth saving, read How to Tell if Canna Bulbs are Good: 5 Simple Checks.

The Curing Process

Curing is a critical step that many gardeners skip, but it makes a big difference in how well the rhizomes store. Curing is simply the process of letting the rhizomes air dry for a few days before putting them into long-term storage. This allows the outer skin to toughen up and any cuts to "callus" over.

Find a dry, well-ventilated spot that is protected from rain and frost. A garage, a shed, or a covered porch works perfectly. Spread the rhizomes out in a single layer on a piece of cardboard or newspaper. Do not stack them, as this can trap moisture and lead to rot.

Let the rhizomes dry for about three to seven days. You will notice the outer surface becoming a bit more firm and the remaining soil turning to dust. This drying period helps prevent fungal growth and rot during the months of storage.

Dividing Canna Rhizomes

One of the best things about cannas is how quickly they multiply. You may find that your original plant has grown into a massive cluster. You can choose to divide these clumps either in the fall after curing or in the spring before planting.

If you choose to divide them in the fall, look for natural breaking points in the clump. Each piece you save should have at least one to three healthy "eyes" or growing points. Use a clean, sharp knife to make the cuts. If you divide them now, it is a good idea to let the cut ends dry for an extra day or two to ensure they have callused over before they go into their storage medium. If you want to expand your planting next spring, the Canna Assorted Mix - Bulk Offer is an easy way to add several colors at once.

Many gardeners prefer to wait until spring to divide their cannas. This is because the eyes are often more prominent and easier to see once the plant is ready to wake up. Either way is fine, and it often comes down to how much storage space you have available.

What to do next:

• Cut back frosted foliage to 3 inches.
• Dig in a wide circle to avoid damaging the fleshy roots.
• Gently rinse or brush off excess soil.
• Air dry (cure) in a protected area for 3 to 7 days.

Choosing a Storage Medium

Canna rhizomes should not be stored completely bare in the open air, as they may dry out too much (desiccate) and shrivel up. To keep them healthy, we recommend packing them in a "medium" that helps regulate moisture.

There are several excellent options for storage materials:

• Peat Moss: This is the most common choice. It is lightweight and holds a tiny bit of moisture while remaining breathable.
• Vermiculite or Perlite: These mineral-based materials are excellent for preventing rot because they don't hold onto excess water.
• Wood Shavings or Sawdust: Often sold as pet bedding, these provide great insulation and airflow.
• Newspaper: You can wrap individual rhizomes in sheets of dry newspaper. This is a very simple and low-cost method.

Avoid using standard potting soil for winter storage. Potting soil is designed to hold moisture for growing plants, which is exactly what you want to avoid during the dormant winter months.

Step-by-Step Packing for Winter

Once your rhizomes are cured and you have chosen your medium, it is time to pack them away. You can use cardboard boxes, plastic bins with air holes, or even heavy-duty paper bags.

1. Start with a Base Layer: Place a two-inch layer of your chosen medium (like peat moss or shavings) at the bottom of the container.
2. Arrange the Rhizomes: Place the rhizomes on top of the medium in a single layer. Try to keep them from touching each other. This ensures that if one rhizome develops a spot of rot, it won't easily spread to its neighbors.
3. Cover and Repeat: Add another layer of medium until the rhizomes are completely covered. If your container is deep enough, you can add a second layer of rhizomes and cover those as well.
4. Label Your Varieties: If you have different colors or types of cannas, be sure to label each box. It is easy to forget which one is the "tall red" and which is the "dwarf yellow" by the time spring arrives.

If you are using plastic bins, do not snap the lid on tight. Rhizomes are living things and need a small amount of oxygen. If the bin doesn't have holes, leave the lid slightly ajar or drill a few small ventilation holes in the sides.

The Ideal Storage Environment

The location where you keep your containers is just as important as how you pack them. Canna rhizomes need a "Goldilocks" environment—not too hot, not too cold, and not too damp.

Temperature

The ideal temperature range for storing canna lilies is between 40°F and 50°F. This is cool enough to keep the plants in a state of deep dormancy but safely above freezing.

Common storage locations include:

• Unheated basements
• Root cellars
• Attached garages that stay above freezing
• Cool closets or crawl spaces

Avoid areas near furnaces, water heaters, or heating vents, as the warmth will cause the rhizomes to dry out too quickly or sprout prematurely. Similarly, avoid unattached sheds where the temperature might drop below freezing during a cold snap.

Humidity and Light

The storage area should be dark. Light can signal to the plant that it is time to start growing, which wastes the energy stored in the rhizome. As for humidity, a moderately dry environment is best. If the air is too damp, you risk mold and rot. If the air is extremely dry (like in a heated home), you may need to check the rhizomes occasionally to make sure they aren't shriveling.

Monitoring Your Rhizomes Through Winter

Storing cannas is not a "set it and forget it" task. For the best results, you should check on your rhizomes about once a month throughout the winter. This simple habit allows you to catch any small issues before they become big problems.

When you check your boxes, look for two main things: rot and desiccation.

Dealing with Rot

If you see a rhizome that feels mushy or has a foul smell, it has started to rot. Use a clean knife to cut away the soft portion until you reach firm, healthy tissue. Let the cut end air dry for a day and then return it to the box. If the entire rhizome is soft, discard it immediately so the rot does not spread to the rest of your collection.

Dealing with Desiccation

If the rhizomes look very wrinkled or feel extremely light and brittle, they are drying out too much. To fix this, use a spray bottle to lightly mist the storage medium (the peat moss or shavings) with a little bit of water. You don't want it to be wet—just a tiny bit of moisture is enough to stop the shriveling.

Key Takeaway: A quick monthly check is the best way to ensure a high survival rate for your stored cannas.

Alternative: Storing Potted Cannas

If you grow your cannas in large pots or containers, you have a convenient "short-cut" for winter storage. You do not necessarily need to dig the rhizomes out of the soil. For smaller spaces, Short Cannas are a convenient option.

Once the first frost hits, cut the foliage back to the soil level just as you would with in-ground plants. Move the entire pot into a cool, frost-free location like a basement or garage. Stop watering the pot completely. The soil in the pot will act as the storage medium and protect the rhizomes from drying out.

In the spring, about six weeks before the last frost, you can bring the pot back into a warm, sunny spot and start watering it again to "wake up" the plants. This method is much faster and is a great option for those with limited time or space.

When to Bring Cannas Out of Storage

As the days get longer and the ground begins to thaw, you can start thinking about the upcoming gardening season. Most gardeners wait until the danger of frost has completely passed before planting cannas directly in the ground.

However, if you want a head start on blooms, you can pot up your stored rhizomes indoors about four to six weeks before the last expected frost date. Place the pots in a warm, sunny window and keep the soil lightly moist. By the time the weather is warm enough to plant outside, you will have established plants ready to grow. If you want a bold striped option next season, Canna Tall Tropicanna is a classic choice.

Before moving them outside permanently, remember to "harden off" your cannas. This means giving them a few hours of outdoor sun each day, gradually increasing the time over a week. This prevents the leaves from getting sunburned or stressed by the sudden change in environment.

Realistic Expectations for Success

While storing canna lilies is a straightforward process, it is important to remember that they are living organisms. Every winter is different, and factors like your home's humidity and the health of the plant at the end of summer will play a role in how many rhizomes survive.

Experienced gardeners are usually very happy with an 80% survival rate. If you lose a few to rot or shriveling, don't be discouraged! It is a normal part of the process. Starting with high-quality, healthy plants from Longfield Gardens gives you the best foundation for a successful harvest and storage season. We back our bulbs with a 100% Guarantee, too.

The effort you put into storing your bulbs in the fall will be rewarded ten-fold when those tropical leaves begin to unfurl in the summer sun. There is a special kind of satisfaction in knowing that the beautiful flowers in your garden are the same ones you carefully tucked away for the winter.

Conclusion

Storing canna lily bulbs for the winter is one of the most effective ways to build a lush, tropical garden over time. By following the natural signals of the seasons—waiting for that first frost and providing a cool, dark resting place—you can preserve these beautiful plants for years to come. The process is simple: dig, cure, pack, and monitor. For more growing basics, read All About Cannas.

We at Longfield Gardens believe that gardening should be a rewarding and accessible hobby for everyone. Saving your rhizomes not only saves money but also allows you to grow larger, more impressive clumps each year. As you pack your cannas away this fall, you can already look forward to the bold colors and dramatic foliage they will bring to your landscape next summer. If you love dramatic foliage, Canna Tall Tropicanna Black is another standout for next season.

• Wait for the first frost to signal the start of dormancy.
• Cure the rhizomes for several days to toughen the skin.
• Store in a breathable medium like peat moss or wood shavings.
• Maintain a temperature between 40°F and 50°F.

Following these steps ensures that your canna lilies stay healthy and ready to sprout as soon as the spring sun warms the soil.

FAQ

Can I store canna bulbs in a refrigerator?

It is generally not recommended to store canna rhizomes in a kitchen refrigerator. Refrigerators are often too cold (usually around 35°F) and the air is very dry, which can cause the rhizomes to shrivel. Additionally, some fruits release gases that can interfere with the health of the bulbs. A cool basement or garage is a much better choice.

Should I wash the dirt off the rhizomes before storing?

You can either wash them or simply brush off the loose soil. Washing makes it easier to inspect for rot or pests, but you must ensure the rhizomes are completely dry before packing them away. If you live in a very humid climate, brushing off the dirt without water may be safer to prevent rot.

What happens if I forget to dig my cannas before the ground freezes?

If the ground freezes solid, the water inside the fleshy rhizomes can freeze and expand, which usually kills the plant. If you experience a sudden deep freeze, dig them up as soon as the soil thaws and check if they are mushy. If they are still firm, they might have survived, but if they are soft and leaking fluid, they likely won't recover.

Do I need to water the cannas while they are in storage?

In most cases, you do not need to water them. The goal is for the plant to remain dormant. However, if you check them and find that the rhizomes are becoming very wrinkled or brittle, you can lightly mist the storage medium with water. The medium should feel barely damp, never wet.